RCA PC41 audio problem

[Phil]

I have been working on this 9PC41 off and on for some time now. The video isn't too bad but I have an audio problem which is very annoying. The audio has a squeal somewhere I would say around 3 kHz that is loud enough to make watching it for any length of time impossible. I've replaced all of the bypass caps, 1500pf with no change. It was my first guess the IF was oscillating but this doesn't seem to be the case. Tuning the IF doesn't effect the pitch although it does change the amplitude. The audio from the TV goes through the radio chassis for tone control and shares the same amplifier chassis as the radio. The radio sounds great.
Anyone have any ideas? Thanks