Allen and Heath saber master section

Hi guys. I recently bought a saber at a rather silly low price. I knew it needed a little work, but I'm really struggling with a couple of things on the master section.

All channels seem fine, but a few niggles on the master are stopping me from using this lovely board in anger.

If I engage the oscillator, and assign to LR mix, both meters show the same signal. However the right channel is intermittently substantially louder. This never seems to happen when the module is outside of the frame . Tapping around the LS volume  pot can cause this level to jump up/ down , but only on the right channel. The left remains consistent although, when the right jumps up, substantially quieter.

Additionally, when the oscillator is engaged, and assigned, the talk back mic is engaged too. Is this normal behaviour on this desk?
Any help you guys can give would be greatly appreciated

Since this console is old, I'd first check for cold solder joints.
Maybe you should reflow all the joints and see if it solves the problem.
And you could replace this pot...

Thanks!

I'll start there.

I was going to replace the ICS in the master section and put sockets in; so I guess whilst the soldering iron is out....

Dude....
THANKYOU.
Re flowed all 3 cards , some of the flimsy top to bottom wires had come away. Now hearing it all loud and clear both sides with no intermittent nonsense! In so doing, however I've managed to break the vu output for the right channel.

Probably just a  wire link that fell through a bit when I heated it up, but I gotta find the damn thing now!

Thanks again