I detected a minor issue with the /e/OS on FP3 and I suspect it might be a bug. Therefore, someone might want to confirm the following behaviour:
I put on music with the VLC media player. Connecting and diconnecting the headphones works fine and the music plays through the headphones or the loudspeaker as wished. As a normal behaviour, VLC pauses the music automatically when you disconnect the headphones.
However, when the FP3 goes into sleeping mode, with the music still playing, disconnecting and reconnecting while still in sleeping mode causes a different behaviour: the music does not resume, as it should. When I wake up the phone and push the play button in VLC to resume the music, the music comes from the loudspeaker although the headphones are connected. Disconnecting and reconnecting the headphones does not have any effect, the music just keeps playing through the loudspeaker. Restarting VLC does not resolve the problem. But, the issue does not persist after rebooting the FP3.
In comparison, when I disconnect and reconnect the headphones in sleeping mode rapidly, the music resumes. Reconnecting after at least five seconds causes the described behaviour.
Also, when I disconnect the headphones in sleeping mode and reconnect them after I have woken up the FP3, everything works ok.
I repeated the experiment many times and the observations are always the same. I tried it out with music from NewPipe Legacy and RadioDroid and the same thing happens. Can someone confirm the aforementioned behaviour replicating the procedures?
To sum up:
As for the initial setup: /e/OS (0.11-2020082870302) on FP3 with VLC media player (3.2.12) from F-Droid (Newpipe Legacy 0.20.2, RadioDroid 0.83). I do not know if there are some parameters in the system settings that might cause the behaviour.
Put on some good vibes with the VLC or some other media player
Check disconnecting and reconnecting the headphones with the FP3 on.
When in sleeping mode, disconnect and reconnect the headphones rapidly.
When in sleeping mode, disconnect the headphones and reconnect them after at least five seconds.
When in sleeping mode, disconnect the headphones. Wake up the phone and reconnect the headphones.
Share your observations.
Hopefully, we can find out if the problem is caused by the phone, the operating system, the music players or a combination of factors. Maybe it is just my FP3 being weird. Who knows?