The Stasis II is great sounding reliable amp. By now, all the electrolytic caps, which aren't many, need to be replaced. Most likely, one had gone totally bad on the affected channels driver board and needs to be replaced.
I recapped, my Stasis II a number of years back in an afternoon with BlackGate Standards which are no longer available, but I understand that Jon has some for his rebuild customers. There are some other great caps available such a Nichicon KZ. I also replaced and significantly upgraded the four large aluminum-can power-supply filter-caps with modern version with the same physical size as the old, but of a higher capacity and higher voltage rating. I bought them from Mouser or Newark, I just can't remember exactly where now, but it take a little research.
Bottom line, the Stasis II is worth rebuilding or at least repairing. If you are use to listen to the Stasis II with old caps, you will be totally amazed at how great it will sound once it has been re-capped. It will truly be a new amp like you have never heard. If you send it to Jon, he will do other things beside replacing caps that will take it a notch better including tweaking the bias to make it perfect. Jon knows that amp better that anyone.
Do a search on the Threshold Stasis II at DIYaudio.com. Lots of information on this amp is found there.
