diyAudio - SoundTech PowerSource1300 NOISE

Hi friends,im a E hobbyst with some test gear,i got this sountech powers source1300(ebay),this one have a noise at the
outputs like a buzz ,everything at the output modules are fine (power trs ,resistors,etc) i put some pics ,the oscilloscope
taken at the outputs with 1khz sinewave at the inputs,and at the power supply with no load (NOTE in power supply i got
same signal at pos,neg hi and low voltage rails,but even at the ground with the ground of the scope at the amp ground..???)

I will try to upload the schematic i get,the noise decrease at outputs when i disconnect one chanel no matter if is A or B

I only notice that the PWM ic's gets really hot ,i change the caps at power supply,one side only,and the signal
in the oscilloscope just 'focus' but the amplitude an freq still are the same (the pictures are taken after the
recap)

Note.

So if anybody can give some advice ,that will be nice,