Can't recieve calls or voice messages

[PSP250]

I have obviously changed one of my settings, I can get calls and voice messages but canot hear they. How do I reverse what I have done?

 

[Titillating]

I'm not sure if there is an option to permanently disable that, but it might depend on your phone and the OS you are running. It's possible that you simply muted yourself during the call or something. If there really is an issue, it's probably more hardware related, perhaps an issue with the mic on your phone. Does it pick up sounds in any other apps, like Skype or other voice chat alternatives?