Weird microphone issue

Helloo all,

I'm new to these forums, and I have a weird issue with my iPhone.
I own a black iPhone 3G (8GB), which works almost perfect whith iOS 4.2 installed. However, I've encountered a very strange issue: when I make a call, everything works fine, microphone, speaker etc. But when I use the voice recorder, or Skype, or any other app, the microphone refuses to work When I use the headphones (with built-in microphone), everything works fine (because I use the microphone in the headphones, of course). I'm 99% sure it has to be a software issue, because the iPhone only has one built-in microphone, right? Which works in a normal call.

Any suggestions?

Thanks in advance,
Rik

 

Thanks for your reply!
Unfortunatly, re-installing the software completely did not solve the problem.
Maybe I should try iOS3 then. I guess it's not a common issue either, which I was hoping for. Also, the genius bar is nog an option for me, as there is no Apple store in my country.

Best regards,
Rik

 

Finaly, I found a sufficient solution for this problem.
Due to cracks in the soldering on the main circuit board of the iPhone,
some features may work improperly. In my case, the microphone did
not work in apps, the wifi broke (greyed out) and the gps was not accurate.
The solution? Simple, but it may sound weird, and in fact, it's a bit tricky, too.
You extract the main circuit board from the iPhone (you can look for a video on Youtube on how to do that). Next, you take that very circuit board and place it in the oven for about 10 minutes on 200°C. This is called reflowing the PCB (printed circuit board). The heat remelts the soldering, thus cracks disappear. Apparently, the transistors, memory etc. can stand the heat of the oven. I tried it, and everything works like a charm for three days now. I did not found this solution on myself, and all credits go to these guys: http://www.youtube.com/watch?v=l1azZWWkmSg

Hope I serve someone well,
Rik