mic, sound, outgoing calls issue on iPhone 4s

Hi there!

There are several threads about the same topic:

https://discussions.apple.com/thread/3402377

6551 views

https://discussions.apple.com/thread/3404857?start=105&tstart=0

4874 views

https://discussions.apple.com/thread/3400145?start=30&tstart=0

1793 views

https://discussions.apple.com/thread/3415710?answerId=16552849022#16552849022

241 views

https://discussions.apple.com/thread/3434439?tstart=240

129 views

The threads all start like this: ...Call shows the timer counting as if the call is progressing but absolutely no ring back and cannot hear the party on the other end when they answer...

Apple, have you got any ideas if this issue is Hard- or Software related?? It seems that many people complaining about this problem!

Thanks in advance!!