A flea market SX 636 initially had lower volume and clarity from right channel which persisted despite 4-5 DeOxit treatments to pots and switches. I was playing it tonight, and after switching speakers to be sure that the right side was still deficient, I noticed that now the left speaker sound is not up to par, the right side sounds great. I had also worked the knobs a few times while experimenting with different speakers. Anyone have any idea what could be going on? Thanks in advance for any help.