Microphone not working on Pixel 6a phones making calls

Bitshifter

On Pixel 6a the microphone does sometimes not work when making calls.

I've setup two identical 6a for my parents (which the've used for years with GOS) and recently this problem occures on both devices.

GrapheneOS version 2024112700.
I've checked the permissions and that mic is not muted.
Speaker mode does not work either
Same problem calling again.
Same problem with other phone app
Making Signal calls works (when previously not workning for regular calls).
No headset involved
A restart solves the problem (for a while)

Mxler

Check if you have VoLTE enabled. Voice calls over 2G can cause issues like this.

If you are in an unsupported country try https://github.com/kyujin-cho/pixel-volte-patch/blob/main/README.en.md

Bitshifter

Mxler Do you mean to set Preferred network type to 4G only?

ZoraIsHere

I saw that in Update 2024120900 some carrier stuff was updated. Did that eventually help?

yellow-leaves

No issues with my Bluejay
4g only

maybe try setting up carrier settings manually

d4er

I also had this issue, but I think it's fixed now. I will report back if it reemerges. Not sure if trouble was from having KDE connect installed and quick tiles not working or I noticed while using g maps or after using it, no mic would work 🤷.

Bitshifter

Ok maybe it has been resolved, no issues the last couple of days, I will report back if it remains.

cache

I am currently experiencing the same exact issue as OP.

Pixel 6a
GOS 2025011500
VoLTE confirmed on

The issue has been ongoing since the OP. All symptoms match OP.

Bitshifter

Problem has reemerged on both devices on my first post.

New tests when mic not working.
Build 2025011500

Phone settings

Roaming on
4G Calling on
Preferred network 5G
WiFi Calling enabled
Allow 2G enabled
WiFi connected

Action: Disabled 4G Calling
Call not possible, no cellular network.

Action: Enabled 4G Calling
Action: Disabled WiFi calling
Mic works

Now I can enable any of the above and the mic works.

Maybe the disabling/enabling of 4G Calling reset something.