The CD that came with the device listed RTL8671B, but it's not on Realtek's website. Instead the manual points you to:
https://www.mytechkey.com/pages/driver
4.Bluetooth 5.0 Dongle
Driver Link:
https://www.dropbox.com/s/gwo9lz777i82f70/BT5.0%20Driver.zip?dl=0
Hope that helps someone.
https://github.com/peteristhegreat/drivers-backup/releases/tag/1.0
Direct link
https://github.com/peteristhegreat/drivers-backup/releases/download/1.0/BT5.0.Driver.zip
Adding visibility to @carkrueger 's comment below
If you look here: https://www.catalog.update.microsoft.com/Search.aspx?q=realtek+bluetooth+1.6.1015 You will find now: 1.6.1015.3014 from 11.01.2021
Direct download link: http://download.windowsupdate.com/c/msdownload/update/driver/drvs/2021/02/0d13721d-7aa7-47cf-887a-f53bcd228a5e_04c173bad44cec04d528d260392958dc6e5bcec3.cab
for backup purposes: h**ps://web.archive.org/web/20210216175344/http://download.windowsupdate.com/c/msdownload/update/driver/drvs/2021/02/0d13721d-7aa7-47cf-887a-f53bcd228a5e_04c173bad44cec04d528d260392958dc6e5bcec3.cab
Direct download and the popup window for 1.6.1015.3014
didn't initially work. I ended up needing to right click the link and select Save target as
.
For it to work for me on Windows 10, I unzipped the cab file into a folder and then used Device Manager to look at that folder. Worked like a charm.
Just used bluetooth tweaker to connect my android phone to my Bluetooth adapter and streamed music over a2dp. it will only connect at sbc.
then i connected my aac aptx tws headphones to my bluetooth adapter to my pc using the tool and it connected aac. but it does show aptx available.. interesting.
im still trying to figure out for you why windows wouldnt pick aptx low latency as thats the best codec avaiable to you,
i stand corrected though that this device seems to support aptx.. nice find Barleyman
im on the 3020 driver in windows 11 - http://download.windowsupdate.com/c/msdownload/update/driver/drvs/2021/06/5775f5fa-4094-4edf-a4e8-d3b809eed071_6ecc7e4a750ed4e1f90885d598a0d91c8c83f385.cab
to test yourself people download this and pair your device. warning you get one shot at a device in free mode. even after unistalling it locks you into checking 1 device to pick wisely unless you want to purchase. it is only 5$ though so might be worth it :)
https://www.bluetoothgoodies.com/tweaker/