Blackberry auto-disconnects calls after several seconds

[Limescout]

my brother accidentally let his Blackberry Pearl 8130 go through the washing machine. He gave the phone to me, but it seems to be working just fine. The only problem is that whenever I make a call, the call is disconnected about 10 seconds into the call. This is not a service issue, because I have a strong signal. Any help or advice to repair this issue is greatly appreciated!