Weird audio issue

[RMSe17]

I was talking on the phone when I plugged my phone into the power adapter, and the audio in the phone call disappeared. I thought that was strange, and reset the phone, after which the audio worked fine when the phone was plugged into the power adapter, or the USB power adapter, but now audio during the phone will not work without the power adapter.

So.. when I am not on the phone, volume works just fine, but as soon as I go to dial a number and click on connect, or answer a call, my speaker no longer sends any audio. Pushing and holding the talk button no longer enables the speakerphone either. If, while I am in the call, I connect to the power adapter, the audio turns on, but once again, as soon as I disconnect the power adapter, audio is gone.

Sometimes if I reset the device, the first phone call that I make, works fine, but as soon as I hang up, the next call will not work again.

I tried hardware reset, tried WM6, WM6.1, downgraded again to 2003SE, no effect...

Any ideas?

Thanks!