Help Strange volume spikes during call


Up until today, I was sure it was just me who had gotten a defect phone, so I was about to return it. However, I read these reviews and watch how one of the guy who states a couple of bug reports actually fetches my issue as bug no. #3.

3. the in-call volume suddenly "BREAKS & INCREASES" for a second or two while making a voice call, a minor bug that needs to be fixed..

This is exactly my issue. Now, is anyone else out there experiencing this? I wrote a piece here as well, with similar story plus some details regarding whether the issue could be affected of my ancient 2G card or not. Anyways. Would be nice if anyone else here on this forum owned this phone, and could give me a straight verify/deny on that he or she also has had it. If this is the case, it's a software(?) thing and we could just wait for a firmware fix. I recently upgraded my firmware from (default from stock) ~KC1 to ~KC7, which Kies suggested to be the most recent one.

Anyways, your experience on these in-call noise artifacts / volume spikes would be thrilling.