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Please help me to identify this Pioneer Tube amplifier

The chirping is bothersome. It grows louder sometimes and can fry the tweeter /woofer and so i switch off .
This could be from either of the following :

Old caps .
Tube Sockets.
High wall Voltages (237 v here).
Some smaller component /resistors going bad.
Mobile fone interference.
 
Last night i opened up the amplifier.
I removed one OLD large axial elna 200uF 50v cap on the right channel. (The left ch had some electros changed already by the previous owner.)
The chirping continued.

Then i removed the tubes .4 EL34s. They all were cleaned at the their legs and all.
And the sockets were tightened using a flat micro screw driver.
Chirped again !!!

I measured the wall volts . Again high at 237 +_ 2v.

Well...When does it get quiet :
I noticed the other night , the wall volts were 233v and it didnot have the chirping. And I managed a longer session without a single chirp.....
Can someone point me to fix it at home.
Ultimate solution comes from the tech , i know. But.....
 
Microphonic preamp tube maybe? Try to swap the preamp tubes from one side to the other. If noise follow changes, microphonic or problematic tube.
 
It’s still hard to see what’s going on underneath without a picture of the whole amp from below. Can you do that? There look to be a number of the grey paper in oil caps that could be problematic, and there could be resistors that need checking too.

Hard to know what the ‘chirp’ sound is, possibly very slow oscillation? My Pioneer SX82 needed to have a lot of passive components replaced before it was okay (right voltages and quiet). If you could post a short audio recording of the chirps that might move things along too.
 
Dandy...i did that .but now im scared of turning it on as one of its smaller tubes start with a large glow and fades down to the routine intensity in 2 or 3 seconds. Plus there was a little ticking sound from the driver tubes area. Im thinking its the same tube .
I have not turned it on for over a week.
Yesterday i checked the volts in the circuit after a brief switch ON. The affected tube area showed a 467 volts in the open wires that were decreasing slowly by the second whereas the other half had zero volts.

I will have it seen by the tech . But input is always welcome from AK
 
Many Japanese and Euro small signal tubes flash like that. It doesn't indicate any problem.

Voltages won't read properly unless its actually on for a little bit. Tube rectifiers take a little time to conduct and the other tubes have to warm up in order to settle things out to normal. If this still has all the grey caps on the bottom, thats probably what ails it. Those are known to be unreliable.
 
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