Could you be more specific? If you are one of the hundreds with -disorted- audio from P80, you most likely have the well documented capacitor problem. (similar issue with SW-1 SW-1S etc.)
Go here:
http://kiwa.com/PRO80.htmlIf you have (really) good soldering skills, you can attempt this on your own. Personally I wouldn't.
Take care,
Craig N4CQR