Can't pair my headphones

[Bene]

On my Fairphone (Gen 6) I can’t even pair my VMK20 headphones (should support 5.0 APTX HD, SBC und AAC). They show up in “add new device”, I can select them, but after a while it just didn’t pair. This is on /e/OS 3.0.2 official.

I just tested on another FP6 with stock Android → there it pairs. So it’s most likely a software problem.
As there was a brief popup of something aptX related on stock Android, I suspect that it’s some problem with the aptX codec.
Also to debug, I went into developer options and wanted to switch codecs, but the field is greyed out.

This is quite a bummer, because I don’t want to get back to stock android, but also I don’t want to buy new headphones just to be able to hear music on a brand-new phone.

Similar problem here (maybe releated, maybe not): 🎧 AptX unusable on the Fairphone 5

[Jets]

Did you enable debugging by tapping on the build number seven times?

[aibd]

@Bene

Also to debug,

Perhaps you could collect a log of the pairing and what may be happening.

• Capture a debug information from /e/OS

• [HOWTO] log app errors with LogFox on-device to create bugreports

  • You don’t mention it but do the headphones require their own app? This can sometimes be a problem that the app can become crippled if it relies on Google in some way.

[Bene]

So yeah, I ran logcat and had a look into it. Turns out some Gadgetbridge logs also appear (I tried to connect it there too).
So to rule out Gadgetbridge as problem, I uninstalled it. Turn out, this was the issue and now I can pair the headphones again.

Thanks for your suggestions, they pointed me into the right direction.