Enable High Quality mode on your headphones (Updated for macOS Catalina)

change-codec.md

If you're using a high-end bluetooth headset on your Macbook Pro it's likely your mac is using an audio codec which favors battery efficiency over high quality. This results in a drastic degradation of sound, the SBC codec is the likely culprit, read more about it here.

Find out what codec you're using

1. Play a song on your headphones
2. Option (⌥) click the Bluetooth button at the top of your screen
3. If you're using AAC or aptX, you can stop here—those are the highest quality codecs.

Change your codec to AAC or aptX

UPDATE: It looks like Apple has silently dropped support for aptX, leaving only AAC

You'll need to download Apple's Bluetooth Explorer in order to change codecs.

1. Head over to Apple's Developer Downloads

2. Search for additional tools and download Additional Tools for XCode 11.dmg

3. Open the dmg, and open Bluetooth Explorer

4. Click on Tools > Audio Options and change your audio codec to the following settings:

   • Enable AAC
   • Force use of aptX
   

5. Disconnect your Bluetooth headset, reconnect it, and while some music is playing, inspect your codec. It should now show either AAC or aptX.

   

Squeezing the most out of AAC

You can increase the AAC bitrate in Audio Options but be sure to keep an eye on the graphs. The retransmission percentage is roughly equivalent to packet loss, and if you increase the bitrate too high your audio will start cutting out:

The retransmission rate is a function of distance and interference, and you'll need to disconnect/reconnect on each attempt before you find the sweet spot.

BT Receptor UGREEN-40759P

A2DP configured at 44.1 KHz. Codec: AAC-LC, VBR max: 256 kbps. 1 frames * (12+744) bytes = 756 per RTP (max=879) every 23.22 ms

Enabled:
sudo defaults write bluetoothaudiod "Enable AptX codec" -bool true
sudo defaults write bluetoothaudiod "Enable AAC codec" -bool true

Verify with:
sudo defaults read bluetoothaudiod