Hi everyone,
Could someone using a Fairphone 6 running /e/OS Murena please try making a regular (non-VoIP) phone call using USB-C wired headphones?
I’d just like to check whether it works for you, or if this is a more general issue.
Thanks in advance for your feedback! 
Hey, TLDR: It doesn’t work.
I tried it and was disappointed to see (or rather hear) it is not working. It is really messed up. I don’t hear anything, but occasionally sound comes from the phone for a very short split second. I tried it with a small basic Samsung-adapter and a quality DAC from Creative. Both do not work for normal calls but everything else I tested. Also loudspeaker can’t be enabled, it drops back to disabled after a second.
Hi,
Thank you so much for testing and confirming!
Your experience sounds exactly like mine — the phone tries to switch between speaker and internal mic every second, but never activates the USB-C headphones. I also noticed the same glitch with the speaker button turning off automatically after a second.
This really seems to be a serious bug affecting standard (non-VoIP) calls on /e/OS with USB-C audio. Everything else works fine for me too (WhatsApp calls, YouTube, etc.), so the audio system is functional in general — just not for GSM calls.
I hope someone from the /e/OS team or Fairphone community sees this and can point us toward a fix or at least acknowledge the bug.
I found this over a year old forum-post on /e/OS about the Murena One phone. The OP describes the exact same issue. Unfortunately nobody ever replied and it is closed now.
Since I use the USB-C port for my headphones, I am glad you made me aware of that issue. I would’ve probably lost my mind if I unexpectedly run in into this issue. 
Especially because I can’t find any other conversation online about this. In fact, if I google it, the first result is your post. 
Here is a guide how to report issues to /e/OS if you choose to do so. I considered it but I rather wait for LineageOS than joining the Murena-community, since I don’t really like Murena’s way of doing “things”. It’s just that /e/OS is the only de-googled option for FP6 atm.
I am just opening the box start configuring my new fairphone 6+ e/OS Murena.
Came in to this conversation too soon before I make some test with the headphones how they work with a cable and with out it.
The thing is that I have a Fairphone 3 with Android on it, and still it has problems on communications when switching from a call to headphones and also with the loud speaker, when changing from only sound call to video call, the sound it is not loud, difficult to get… so sometimes I have to call again having already the headphones switched in.
I think it s a hardware problem or an android or software problem dealing with the hardware applience.
I am hopping this will change with the brand new phone.