Panasonic SG-3220 Turntable Speed Problem


I recently bought an old Panasonic SG 3220 stereo system, mainly for the turntable. It is fairly old but all parts appear in good shape.

It ran fine at first, but with slight speed variances every now and again (maybe once or twice a record). I got a new belt for it, thinking that would be it. It worked fine for a few weeks, but then got worse.

At first records would speed up at random points, and could be coerced back to speed by flicking it up to 45 then back to 33. This got worse and now it plays slightly fast at 33 and slightly slow at 45 from the off.

It has also developed a low fast clicking in the left speaker when the spindle is going, and occasionally the spindle needs a nudge to start up.

I've had a look at similar threads but my electronics GCSE 6 years ago has not left me with enough knowledge to take general advice and apply it. I took the bottom off to have a gander but couldn't spot anything on my own.
If anyone's got any ideas about how to get it back in line that would be very helpful.