[Kenwood] TS-940 AGC

[art davis]

After 22 years of use, my 940 has developed it's first problem. It seems that the AGC has gone south (distorted audio, s-meter readings S9+60 on average signals, and the AGC switch has very little if any effect) but only in the USB/LSB modes. All other modes/functions seem to be working normally.  Is the AGC circuitry different for SSB and CW? Can someone point me in the right direction?

Thanks, Art
N4UC