Recently (probably in the last two weeks or so) my pioneer amp has stopped working in stereo... I have tried the obvious things (ie. switching speakers, switching speaker ports etc) It seems like the amp will play in stereo very sparsely then cut out on the right side. I was not able to replicate the problem on either port on the left side.When i switch the amp to mono, both speakers work. The problem persists on all the inputs (phono, aux etc.) Any ideas what is causing the problem or how to fix it?