Restart Bluetooth Daemon on Mac OS X without restarting

restart_bluetooth.sh

#!/bin/bash

sudo kextunload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport
sudo kextload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport

Works like a charm, thanks!

👍 Thanks!

Thanks! =)

Thanks.. it works!!!

Thanks.. It works 👍

Thanks!!!!

Does not work on El Capitain... First command crashed OS X and caused a reboot.

My El Capitain didn't crash or reboot but still did not work.
First command yielded:

(kernel) Can't unload kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; classes have instances:
(kernel)     Kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport class BroadcomBluetoothHostControllerUSBTransport has 1 instance.
Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) kext is in use or retained (cannot unload).

and second command just turned off my bluetooth without the ability to turn it back on

👍

@zakiaziz: were you able to figure this out? I'm facing the same issue.

Thanks! works fine on Yosemite

Thanks!

Not working in El Captain
❯❯❯ sudo kextunload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport ⏎ ⬆ ◼ (git:ir_646)
Password:
(kernel) Can't unload kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; classes have instances:
(kernel) Kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport class BroadcomBluetoothHostControllerUSBTransport has 1 instance.
Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) kext is in use or retained (cannot unload).

Thanks!

Works great!

works fine with 10.10.5 Yosemite

Thanks!

WOOT. Thank you.

perfect! (10.10.5)

worked perfectly (10.10.5)

worked perfectly (10.10.5)

As others have said, fails completely on 10.11.5 (El Capitan).

I couldn't find a similar solution on 10.11 (El Capitan), so i decided to restart the whole Bluetooth Module. Should work in upcoming versions too. See this gist: https://gist.github.com/ralph-hm/a65840c4f5e439b90170d735a89a863f

As others have said, fails completely on 10.11.5 (El Capitan).

Beware: Failed for me too on El Capitan.

A GUI version:

Do not work on El Capitan

Worked for me on Yosemite (10.10.5). Thanks.

Awesome..! Worked like a charm..! Thanks.

Awesome!

Thank you @nicolasembleton!
I added turn on/off option to this script if someone also needs it.
https://gist.github.com/0xfib/d008370c49a37f7051b1afef8567fefd

Nice!

It works!!!

I've got a jagged line through the bluetooth icon in the menu bar, this doesn't work for me unfortunately.

(kernel) Can't unload kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; classes have instances:
(kernel)     Kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport class BroadcomBluetoothHostControllerUSBTransport has 1 instance.
Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) kext is in use or retained (cannot unload).

Just what I needed. And it works, too. :-) Thanks!

Flawless, just what i needed after bluetooth stopped working after a wake up from sleep

Works for me, thanks!

Worked for me! Yosemite 10.10.5. Thank you!

Worked on MacOS Sierra 10.12.3. Thanks!

Just saved me rebooting even after shift-option click to restart the BT module via debug menu didn't work. Thanks!

Thanks!

Thank you!

Works on Sierra.
Thanks, sometimes the bluetooth crashes

Worked perfectly for me, thanks!!
I'm using Yosemite 10.10.5

Doesn't work on El Captain! Restart needed.

El Capitan 10.11.6:
(kernel) Can't unload kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; classes have instances: (kernel) Kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport class BroadcomBluetoothHostControllerUSBTransport has 1 instance. Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) kext is in use or retained (cannot unload).

Thanks! Worked perfectly on Yosemite 10.10.5

Thank so much!

Thanks much!

Working for me on Sierra 10.12.6.

Plus fixes my magic mouse connection issue instantly. :-)

High Sierra:

(kernel) Can't unload kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; classes have instances:
(kernel)     Kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport class BroadcomBluetoothHostControllerUSBTransport has 1 instance.
Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) kext is in use or retained (cannot unload).

Need solution for high sierra, after sleep Bluetooth dead until restart

High sierra, pain in the ass. Anyone know this trick for this OS?

you saved me a reboot, thanks a lot !

First command:

$ sudo kextunload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport
Password:
(kernel) Kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport not found for unload request.
Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) not found.

on Sierra, 10.12.6, MacBook Pro (13-inch, 2016, Two Thunderbolt 3 ports)

I don't get why this seems to work only for ~50% of people as I see about the same amount of "thanks" as "doesn't work for me" messages here... anyone got an idea?

Answering myself:

kextfind -loaded | grep -i blue

reveals that on my MacBook there are different dirvers loaded.

Unloading them "works", but I have to explicitly unload IOBluetoothHostControllerUARTTransport and IOBluetoothHostControllerTransport

like

sudo kextunload -b com.apple.iokit.IOBluetoothHostControllerUARTTransport
sudo kextunload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport

Bluetooth devices /keyboard, trouchpad)stop working as expected.
On loading them again (replacing unload with load in the previous command), screen blacks out and system seems to do a warm restart.
Bluetooth works after that again for keyboard and external touchpad, but the bleutooth speaker, for which I tried toi do this all, still doesn't work, even though it always used to work for months now, and just this morning stopped being available as audio device, while being shown as connected as bluetooth device.

Great! it works like a charm!

@henning, I agree. This used to work without fail but seems to be intermittent now; and comes with the error you're seeing. Haven't done much testing but hopefully people will SEE THIS MESSAGE and post what OS version their running, along with the device (from the  menu > about this mac)

System Version: macOS 10.13.1
Model Name: MacBook Pro
Model Identifier: MacBookPro10,1

this is fantastic! Thanks so much 👍

I love you!

I was having an issue and getting the "failed to unload" error as well. I had my trackpad plugged in via USB though. As soon as I unplugged the trackpad and ran the command again, I got the same error, but the bluetooth services reset themselves and my trackpad connected via Bluetooth again.

@gbmeuk & @henning,
my details:
System version: 10.13.2
Model Name: MacBook Pro
Model Identifier: MacBookPro10,1

Issue: Currently experiencing trouble with reconnecting my bluetooth headset and even the bluetooth process on my Mbp looks like it is not finding any other bluetooth devices (tried other devices like my smartphone etc). In most situations (putting my mbp to sleep) the issue of reconnecting my headset starts. Now normally a reboot of my OS is sufficient too re-align the processes in the correct order. But even that won't do the trick atm. I found this script and the alternate version that @0xfib shared. both version don't seem to be working, getting the same return values as reported by other users. Are you guys currently anyway closer to a solution?

Returned values:

./bluetooth_restart.sh
(kernel) Can't unload kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; classes have instances:
(kernel)     Kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport class BroadcomBluetoothHostControllerUSBTransport has 2 instances.
Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) kext is in use or retained (cannot unload).
Bluetooth restarted

Getting error on macOS 10.13.3

./restart_bluetooth.sh 1

(kernel) Can't remove kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; services failed to terminate - 0xdc008018.
Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) kext is in use or retained (cannot unload).
Bluetooth is on

macOS 10.13.4 works fine here to fix my bluetooth speaker connection

$ sudo kextunload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport
(kernel) Can't unload kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; classes have instances:
(kernel)     Kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport class BroadcomBluetoothHostControllerUSBTransport has 5 instances.
$ sudo kextload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport

The more you do this, the more the number counts up

$ sudo kextunload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport
(kernel) Can't unload kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; classes have instances:
(kernel)     Kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport class BroadcomBluetoothHostControllerUSBTransport has 6 instances.
$ sudo kextload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport

Let's get to 2,147,483,647?

This might also help:

sudo launchctl stop com.apple.bluetoothd;sudo launchctl stop com.apple.diagnosticextensions.osx.bluetooth.helper;sudo launchctl stop com.apple.bluetoothReporter;sudo launchctl stop com.apple.IOBluetoothUSBDFU; sudo launchctl stop com.apple.bluetoothaudiod;sudo kextunload -v 6 -b com.apple.iokit.IOBluetoothFamily;sudo kextunload -v 6 -b com.apple.iokit.IOBluetoothHostControllerTransport;sudo kextunload -v 6 -b com.apple.iokit.IOBluetoothHostControllerUSBTransport;sudo kextunload -v 6 -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport

I found a even better solution.
Turn Bluetooth+Wifi off, then turn Wifi+Bluetooth on.
Works perfectly for me every time :-)

@uyjulian Thank you! It works!

@uyjulian's solution worked for me on High Sierra 10.13.5. Thank you!

codes above gives following response:

(kernel) Can't remove kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; services failed to terminate - 0xxxxxx.
Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) kext is in use or retained (cannot unload).

but this blueutil works for me on 10.13.5.

High Sierra 10.13.5 (MBP 13 Early 2015)
https://github.com/max-lobur/dotfiles/blob/master/sh/bt.sh - managed to fix like this

One solution which works for me on High Sierra is to kill the bluetooth daemon. It auto restarts which seems to sort it out. Here's a one liner (note it has to be done under sudo because the bluetoothd process isn't owned by $USER):

sudo kill -9 `pgrep bluetoothd`

➜ ~ ./restart_bluetooth.sh
(kernel) Can't remove kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; services failed to terminate - 0xdc008018.
Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) kext is in use or retained (cannot unload).
➜ ~ uname -a
Darwin MacBook-Pro-XXX.local 18.0.0 Darwin Kernel Version 18.0.0: Sun Jun 10 19:23:56 PDT 2018; root:xnu-4903.200.249~5/RELEASE_X86_64 x86_64
➜ ~ system_profiler SPSoftwareDataType
Software:
System Software Overview:
System Version: macOS 10.14 (18A314k)
Kernel Version: Darwin 18.0.0
Boot Volume: Macintosh HD
Boot Mode: Normal
Computer Name: XXX
User Name: XXX
Secure Virtual Memory: Enabled
System Integrity Protection: Enabled
Time since boot: 5 days 1:43

Thanks!

I'm on sierra and was getting the same 'Can't remove ...' error. You can just hold Shift+Option and click on the Bluetooth Icon Top Menu, It will reveal an option called Debug Menu item that has a Reset the Bluetooth Module option.

If you need to do this in terminal for some reason, stackoverflow suggests.

sudo launchctl stop com.apple.blued
sudo launchctl start com.apple.blued

A Comprehensive Solution

/usr/local/bin/blueutil -p 0 alone didn't work for me, I did this:

~/.local/bin/restart-bluetooth:

#!/bin/bash

# Docs I read
# https://gist.github.com/nicolasembleton/afc19940da26716f8e90
# https://gist.github.com/ralph-hm/a65840c4f5e439b90170d735a89a863f
# https://github.com/max-lobur/dotfiles/blob/master/sh/bt.sh

# Things I had to do beforehand
#brew install blueutil
# Restart bluetooth every time good ol' lappy wakes up:
#brew install sleepwatcher
#sudo mkdir -p /usr/local/sbin
#sudo chown -R $(whoami):staff /usr/local/sbin/
#brew link sleepwatcher
#/usr/local/sbin/sleepwatcher --verbose -w ~/.local/bin/restart-bluetooth
#brew services start sleepwatcher


# Stop all the bluetooth stuff
sudo kill -9 $(pgrep bluetoothd)
/usr/local/bin/blueutil -p 0
sudo kextunload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport
sudo kextunload -b com.apple.iokit.IOBluetoothHostControllerUARTTransport
sudo launchctl stop com.apple.blued

# Start enough of the bluetooth stuff
/usr/local/bin/blueutil -p 1
sudo launchctl start com.apple.blued
sudo kextload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport

It's only sometimes that my bluetooth doesn't reconnect after sleep & wake (may be related to docking to my Thunderbolt Display) and I don't know how to immediately cause the problem, so I don't know what about that process is required. Obviously some of it is superfluous, but if I run that script my bluetooth dies and comes right back, so I know it's working well enough.

If someone can pare it down to just what's necessary I'd love to hear the explanation (ping me @coolaj86).

Awesome!!! Thanks!!!

@will-dee thanks, your solution worked for my Hackintosh!!

I've got a jagged line through the bluetooth icon in the menu bar, this doesn't work for me unfortunately.

(kernel) Can't unload kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; classes have instances:
(kernel)     Kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport class BroadcomBluetoothHostControllerUSBTransport has 1 instance.
Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) kext is in use or retained (cannot unload).

Same

+1

Ahhhh still works like a charm Mac OS Sierra

Thanks @coolaj86

I've got a jagged line through the bluetooth icon in the menu bar, this doesn't work for me unfortunately.

(kernel) Can't unload kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; classes have instances:
(kernel)     Kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport class BroadcomBluetoothHostControllerUSBTransport has 1 instance.
Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) kext is in use or retained (cannot unload).

Same

Same +1

worked for me

I've got a jagged line through the bluetooth icon in the menu bar, this doesn't work for me unfortunately.

(kernel) Can't unload kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; classes have instances:
(kernel)     Kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport class BroadcomBluetoothHostControllerUSBTransport has 1 instance.
Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) kext is in use or retained (cannot unload).

Same

Same +1

Same +1
Have 2 x 15" macbook pros 2012/2013 and since being on 10.14 does it quite often after waking from sleep. Reboot only way to fix :(

I've got a jagged line through the bluetooth icon in the menu bar, this doesn't work for me unfortunately.

(kernel) Can't unload kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; classes have instances:
(kernel)     Kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport class BroadcomBluetoothHostControllerUSBTransport has 1 instance.
Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) kext is in use or retained (cannot unload).

Same

Same +1

Same +1

@uyjulian restart wifi & bluetooth works Thank you!

@uyjulian solution worked on Sierra 10.12.6
it appears to have conflict with Wifi. will investigate further

anybody aware of a solution that works for Mojave 10.14.1?

@stefandemi +1

I kept coming back to this and finally stumbled on this answer on stackoverflow:
https://stackoverflow.com/questions/17345305/unload-kext-which-still-has-instances

Using the method there I saw that com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport is referenced by com.apple.iokit.BroadcomBluetooth20703USBTransport and that is why it can't be unloaded. Looks like unloading them in dependency order and loading them in reverse order works correctly.

This is the script I'm now using that seems to work for me:

#!/bin/bash
sudo kextunload -b com.apple.iokit.BroadcomBluetooth20703USBTransport
sudo kextunload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport
sudo kextload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport
sudo kextload -b com.apple.iokit.BroadcomBluetooth20703USBTransport

There's also a fuller version that reconnects any previously connected devices using blueutil:

#!/bin/bash
devices=$(blueutil --paired | grep -v "not connected" | awk -F '[ ,]' '{print $2}')
sudo kextunload -b com.apple.iokit.BroadcomBluetooth20703USBTransport
sudo kextunload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport
sudo kextload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport
sudo kextload -b com.apple.iokit.BroadcomBluetooth20703USBTransport
for device in $devices; do
    for retry in {1..5}; do
        if blueutil --connect $device 2> /dev/null; then break; fi
        sleep 1
    done
done

None of these things worked for me - I was forced to reboot my mac in order to get bluetooth working properly again.

I'm on a MacBook Pro (15-inch, 2018) running Mojave 10.14.4

None of these things worked for me - I was forced to reboot my mac in order to get bluetooth working properly again.

I'm on a MacBook Pro (15-inch, 2018) running Mojave 10.14.4

None of these things worked for me - I was forced to reboot my mac in order to get bluetooth working properly again.

I'm on a MacBook Pro (15-inch, 2018) running Mojave 10.14.4

@mgguinne Looks like Apple is breaking "vintage" Macs to sell more new ones. No sale.

None of these things worked for me either, I'm on a 2015 Macbook pro 13'' with Retina Display and have had this problem since 2015. Currrently on 10.13.5...

None of these work here. Latest MacOS

This worked for me (tried it once so far):

https://apple.stackexchange.com/questions/251842/how-to-restart-bluetooth-service-from-command-line
Edit: Bluetooth bugged again, seems like I have to sudo the command to restart it properly or maybe it's just a coincidence.

If you have blueutil installed ($ brew install blueutil), the following script will do the magic on latest MacOS:

#!/bin/bash

echo "Restarting bluetooth service..."
blueutil -p 0 && sleep 1 && blueutil -p 1

echo "Waiting bluetooth service to be restored..."
until blueutil -p | grep "1" >/dev/null; do sleep 1; done

echo "Searching for devices not connected..."
devices=($(blueutil --paired | grep "not connected" | awk -F '[ ,]' '{print $2}'))
echo "Found ${#devices[@]} recently paired devices not connected"

for device in ${devices[@]}; do
    for retry in {1..5}; do	
    	echo "Trying to connect to ${device} ..."
        if blueutil --connect ${device}; then break; fi
        echo "Failed to connect to ${device}"
        sleep 1
    done
done

Also available: https://gist.github.com/thiagoghisi/50c3ba835ea72cdb0318fb3306fd2c76

If you have blueutil installed ($ brew install blueutil), the following script will do the magic on latest MacOS:

#!/bin/bash

echo "Restarting bluetooth service..."
blueutil -p 0 && sleep 1 && blueutil -p 1

echo "Waiting bluetooth service to be restored..."
until blueutil -p | grep "1" >/dev/null; do sleep 1; done

echo "Searching for devices not connected..."
devices=($(blueutil --paired | grep "not connected" | awk -F '[ ,]' '{print $2}'))
echo "Found ${#devices[@]} recently paired devices not connected"

for device in ${devices[@]}; do
    for retry in {1..5}; do	
    	echo "Trying to connect to ${device} ..."
        if blueutil --connect ${device}; then break; fi
        echo "Failed to connect to ${device}"
        sleep 1
    done
done

Also available: https://gist.github.com/thiagoghisi/50c3ba835ea72cdb0318fb3306fd2c76

Thanks @thiagoghisi that worked really well for me :)

Might be good to post to https://apple.stackexchange.com/questions/251842/how-to-restart-bluetooth-service-from-command-line as well as lot's on there are still having issues etc. Seems for some the kextunload/kextload works but for me never worked.

Thanks. This is still useful for my MBP 2013 late.

i got the "failed to unload error"... presumably because it was already unloaded and just needed to load via step 2... which #workedforme :D

10.13.6 High Sierra on late-2013 15" Retina MBP

My result:
"Bluetooth: Not Available"

First command failed for me because something was "already in use or retained" but I went ahead and ran the second command anyhow, then started Bluetooth - and everything worked! Thank you!

worked fine. although I might add that I had a stuck (>20% cpu usage in activity monitor and no audio whatsoever playing or connected via bt) bluetoothaudiod service and killed that first.

Then the op first command gave this:
(kernel) Can't remove kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; services failed to terminate - 0xe00002c7. Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (iokit/common) unsupported function.

But the second command went without a hitch and now I have a working bt audio again without restarting. Good. & thanks! mojave latest version.

Still works great on Mojave. Had a similar issue as some other people with unloading the daemon giving me an error, but then loading it again worked fine. Will reboot at some point here but this is really handy when your bluetooth bites the dust and you'd really prefer not to reboot just yet.

I am having this issue nearly every day now, nothing I do works. I have to reboot. Making me think to fix = new mac 👎

➜  ~ sudo kextunload -b com.apple.iokit.BroadcomBluetooth20703USBTransport
sudo kextunload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport
Password:
(kernel) Can't unload kext com.apple.iokit.BroadcomBluetooth20703USBTransport; classes have instances:
(kernel)     Kext com.apple.iokit.BroadcomBluetooth20703USBTransport class BroadcomBluetooth20703USBTransport has 4 instances.
Failed to unload com.apple.iokit.BroadcomBluetooth20703USBTransport - (libkern/kext) kext is in use or retained (cannot unload).
(kernel) Can't remove kext com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport; services failed to terminate - 0xdc008018.
Failed to unload com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport - (libkern/kext) kext is in use or retained (cannot unload).

The below is the closest that might work, but I might have run some other commands first as Bluetooth now shows "Not Available". Will have to test next time it fails.

sudo kextunload -b com.apple.iokit.BroadcomBluetooth20703USBTransport
sudo kextunload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport
sudo kextload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport
sudo kextload -b com.apple.iokit.BroadcomBluetooth20703USBTransport

My Bluetooth devices.

➜  ~ kextfind -loaded | grep -i blue                                               
/System/Library/Extensions/IOBluetoothFamily.kext
/System/Library/Extensions/IOBluetoothFamily.kext/Contents/PlugIns/BroadcomBluetooth20703USBTransport.kext
/System/Library/Extensions/IOBluetoothFamily.kext/Contents/PlugIns/IOBluetoothSerialManager.kext
/System/Library/Extensions/IOBluetoothFamily.kext/Contents/PlugIns/IOBluetoothHostControllerUSBTransport.kext
/System/Library/Extensions/IOBluetoothFamily.kext/Contents/PlugIns/BroadcomBluetoothHostControllerUSBTransport.kext
/System/Library/Extensions/IOBluetoothFamily.kext/Contents/PlugIns/IOBluetoothHostControllerTransport.kext
/System/Library/Extensions/IOBluetoothFamily.kext/Contents/PlugIns/IOBluetoothUSBDFU.kext
/System/Library/Extensions/IOBluetoothFamily.kext/Contents/PlugIns/IOBluetoothPacketLogger.kext
/System/Library/Extensions/AppleTopCase.kext/Contents/PlugIns/AppleHSBluetoothDriver.kext
/System/Library/Extensions/IOBluetoothHIDDriver.kext

uname -a
Darwin MacBook-Pro.local 19.6.0 Darwin Kernel Version 19.6.0: Sun Jul  5 00:43:10 PDT 2020; root:xnu-6153.141.1~9/RELEASE_X86_64 x86_64

system_profiler SPSoftwareDataType
Software:

System Software Overview:

  System Version: macOS 10.15.6 (19G73)
  Kernel Version: Darwin 19.6.0
  Boot Volume: Macintosh HD
  Boot Mode: Normal
  User Name: mgguinne
  Secure Virtual Memory: Enabled
  System Integrity Protection: Enabled
  Time since boot: 1 day 23 minutes

My bluetooth connected device, for audio, keeps connecting/disconnecting.

I don't have the answer to the problem but I can tell that the process /usr/sbin/bluetoothaudiod keeps restarting (maybe it crashes and restarts) or whatever. I can tell because I'm running while 1; do pgrep bluetoothaudiod; sleep 1; done and there is a PID, then there isn't, then there is another PID, rinse and repeat...

A few notes about the topic that might be some help to somebody:

• Maybe Music (formerly iTunes) or iTunes, depending on your OS version, is causing the problem. I've been struggling for about an hour now with this and after quitting Music the problem is gone. Although note that I did try a bunch of commands before but it seemed that none worked, sound to BT was restored once I closed Music.
• I just found out that bluetoothaudiod is only live while an audio device is connected. When disconnecting the device pgrep bluetoothaudiod doesn't return anything.
• Along with the previous bullet, another thing that might have worked (I doubt it) is that I opened 'System Information' (Apple Menu > About This Mac > System report).
• I don't want to restart my Mac but... when I've tried, the problems goes away. So I would love to have a solution. The use case is as follows: you're using your mac to work (or whatever) and want to hear some music, BT keeps disconnecting so you have to either not use BT or restart, which will kill your workflow.
• Even though audio connects/disconnects my Magic Mouse keeps working.
• This might help How to fix Bluetooth headset audio issues on macOS Catalina?, read the link but basically the options here are:
  • Disable Ask Siri and Turn off Voice Control feature
  • Reset NVRAM

I hope there is some straightforward solution to this... 😕