Mic doesn't work on normal calls (works in WhatsApp, signal)

[yvmuell]

FPOS is not tested/supported with US provider thus can cause issues for US user

Read this topic, I think it was mentioned there several times for the FP4.

Fairphone owners in the USA (FP2 FP3 FP4 FP5)

Hey, funny enough I had that same issue in the USA when I was on the stock rom. After a reboot, this basically happened. The workaround was to turn on speakerphone for a second and switch it off again. Then the mic would work fine for me until I reboot again. No clue if it was in any way related to VoLTE also not working at that moment. This problem has completely disappeared for me when moving to LOS (including VoLTE which is now working). (just realized this is exactly described in Fairphone…