Odd call quality issues

[thatguyfromvienna]

I have an odd issues with my Galaxy S3.
Sometimes, call quality is so poor that understanding the other person is impossible.
The other person sounds overly amplified and somewhat tinny.
When this happens, it happens from the very start of the call.
I cannot reproduce this problem but it only happens when I actively start the call.
It happens when I have good or poor coverage, right after rebooting the phone or when it was running for some days.
Rebooting then does sometimes fix the problem, sometimes it's still there after reboot.
The only way to properly get rid of this issue is to call a random service number with a recorded message a couple of times until the sound is normal again.
I tried enabling and disabling noise reduction and extra volume in the options which didn't help either.
What I found most interesting is that the phone software is aware of the issue - see the red rectangle in the screenshot.

If anybody can help, I'd be more than happy since this is very annoying.

Cheers
Alex

 

[Ichi_Bear]

How long have you had the phone? Have you done the latest update for the S3? Sometimes phone cases can cause problems. Have you tried doing a factory reset? Sometimes that can solve problems.

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