MTX 1501D repair help

Yes I was checking it on the opamp. You had me probe 4,5,7, and 8. I never looked at or measured pin 6. I was just confused about the message you sent last night, I thought you were referring the the octocoupler not the opamp. Then I read it again later and realized I was mistaken. So yes all the voltages and pics of scope were from the opamp (5532).
 
I replaced that op amp and I definitely have a different wave on 7 then I did before. This is with me feeding the amp 100hz wave. This wave on the scope is right around 300khz and very dim on my CRT for some reason.
 

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I'm not sure why the scope is so dim when measuring that. Also the voltage was a little low so I wired up a older 50 amp power supply that wont act funny and it didnt make a difference. Trying to play audio through the amp it is acting very strange. When I spin the gain I can somtimes get like a pulse of the signal out and can hear a up and down whining sound through the speaker allmost like tuning a am radio. The jumper is off the capacitor.
 
If the speaker pulses DC when you adjust the gain, the THAT 2155 (or whatever they used) could be bad but if you're getting clean audio through to the 5532, it's not a problem (at this point).

Is LED238 constantly lit after a short mute delay?

Resistance from the shunt resistors to the positive speaker terminal (nothing connected to the speaker terminals).

Adjusting the trigger level on the scope may give a better display.

Do you commonly use your scope in the 5-10us range?

Re-set the cal/var knobs for the timebase and vertical amplifier to the cal position.