Call issue (mute) after Android 16/One UI 8 update

[djgusmy85]

Hi everybody,

A few days ago, I updated my S25 to Android 16/One UI 8.
After that, the calls have occasionally gone mute. I speak, but the person on the other side can't hear anything. The microphone works properly because with other apps (e.g. voice recorder), it can be heard normally.
Restarting the phone the calls works for a while, but then the problem recurs.

Has anyone else had the same problem?
How can I fix it?

Thanks in advance.

[Members_BkoW0kb]

I have the same issue here. S25 Base model 256GB, unlocked (no carrier). Started to happen after the ONE UI 8 update. The phone has been purchased from Samsung Online Store directly, and it is currently still under warranty 
Apparently, cleaning the cache partition doesn't help
I can also confirm that other VoIP apps (Telegram, WhatsApp) calls work as expected, tested with the very same caller on the other side.
I also tried to disable the WiFi calling feature, but it doesn't seem to be the cause. 

[roerisi]

I found the solution. Given the persistence of the anomaly, we recommend disabling the 2G network while waiting for a definitive resolution by Samsung technicians, which will occur through the release of a new firmware

[Members_x83fcin]

Same here.

Need to reboot to unmute calls.
Only in the Samsung caller app.
Whatsapp calls are fine

[ryuu23]

Thanks I'm going to try this out, I am in a city so I doubt I'll ever need that option, hope this workaround is viable! Cheers

[djgusmy85]

The firmware S931BXXS6BYIF has been released and I just updated. Let's try.

[vermaraman]

Same issue on Samsung s24+ and fold 6..both after taking updates. The first call to a user is mute to the other side but then I call back again and they can hear fine on second attempt. Has happened with and without wifi calling.. Took latest update, the problem is still persisting.. Is Samsung even listening? Guess they are busy building the next AI phone which will talk to us.. No need to call anyone else, uh!!