Computer doesn't recognize my iphone 4 but iphone is charging

[vintagebxl]

I have a Iphone4
but when calling the micro sometimes stops working, so the other person doesn't hear me any more.
I wanted to connect to itunes but
when i connect to a computer (tried a couple pc's and a mac)
the phone is charging, but my computer doesn't find the iphone (doesn't show up in My Computer).

This used to work before,
and when i plug in my old iphone the computer finds it without a problem.

I removed itunes and installed it again.
I did the resets (7 sec and 20 sec) but nothing seems to work!


What to do?

I guess it's a hardware defect,
if i turn it in they can see it's jailbroken (i can not reset it cause i can not sync).

Can i try 'Reset all settings' and hope they do not see it?



hope you have some good idea's.

 

[uhanrodric]

Reset all settings will take you all the way back to the "Connect to iTunes". So yes you can do that. Did you try putting it in recovery mode while connecting to iTunes?

(Turn phone off. Hold power/standby button and home button. Release power/standby button, but KEEP HOLDING home button. It should kick into recovery mode, and iTunes should pick it up.)