Needing help repairing an Orion HCCA 250 Digital Reference

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When I got this amp the PS FET's on one side were all blown. I replaced all the PS FET's,the PS MPSA06's and MPSA56's, all output transistors, all electrolytic capacitors and the 494. The amp powers up and plays but it the sound is distorted and not producing full sound output/power. I pulled the muting circuit transistors to see if it would make a change and it had no effect on it.
 
It seems my scope is a little temperamental, sometimes I can get a
non-distorted waveform out of it, other times not. Before I bought my scope it sat in someones storage unit for years. Thinking possibly some of the plug connections inside it are oxidized. Anyway, I was messing with it and was able to get the waveform in the photo (the best photo I could get of the screen).


During the above process I noticed the two voltage regulators (circled in the photo) are getting hot.



Both rails are equal.


Both channels are equally distorted.


As to testing the op-amps, will you give me more direction on how to do so?
 

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If I were to say the amp is clipping at about 10v, I would be guessing but it sounds about right.



I do not have +/- 15v on the power supply pins of any of the op-amps. Given that I tested the right pins... See attached photo for the pins I tested and voltages.
 

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