You've either gotten in wet, a small tear in one of the cables, or the speaker
itself has gone bad.
I recommend www.wirelesunlimitedinc.com
, or www.myspace.com/wirelessunlimited
They can help with that and they have parts in stock.
Fast turn around and affordable.
If people can't hear you, then it is 99% chance moisture in the microphone. Check with the guys at the contact above for professional, speedy, and affordable repair.
423-913-0488 M-F 10a-6p EST.