I've got this great amplifier. I have fully recapped it with Silmic II caps and replaced some polyesters with polypropylenes on preamp etc. After recapping I put the amp into use for say 9 months or so. Mostly used on weekends only. It sounds wonderful, but lately I've become bothered by almost non-existent stereo separation. Overlooking this issue the amp works perfectly. When I have the normal setup balance knob works accordingly, there is separation, but almost non-existent. I have measured resistance on stereo/mono -switch and it appears to work well. Also I have deoxited all the controls as best as possible. I have also measured a great bunch of resistors from the main amp and they match between the channels. 2sa798 IC been replaced with matched KSA992 sets. Other transistors and outputs are originals. DC offset is 13mv and 8mv. Bias is set and checked. I don't know if I should even look for anything to fix or is it just nature of the beast? http://audiokarma.org/forums/index.php?threads/c28-lack-of-stereo-separation.800914/ I did this test (post #2): Disconnecting the other source input (CD) and other channel is barely audible when balanced to the other side. Both sides work, but the problem is there when I center the balance knob I hear music from both speakers, even if the one of the input RCA connectors remains disconnected. This is normal for this amp? I have tried to look for similar posts on AK, but nothing stands out. WIth every other amp I have worked on the stereo separation have always been much better, more distinctive. Speakers and CD-source are in good working order. Any help or info is appreciated.