Unbalanced Volume on Rowe 601-07405 Amp

[appleton71]

I hope someone can help with this before I decide to push this juke into a bonfire.

I have a Rowe CTI-1C jukebox with a 601-07405 amplifier.  When I turn up the volume past a low level, the right channel gets much louder and extremely bright (very high treble).  The balance control knob seems to have very little effect as it doesn't shift the sound from one channel to the other. 

I'm also having an issue with the sound cutting out all together.  I replaced the cable between the amp and turntable because it looked ratty but it didn't help.  Jiggling other connections doesn't help either but lightly tapping the transistor heat sink does, albeit only temporarily.

Any ideas would be greatly appreciated before I go insane.