I have the ProMedia 5.1 humming/buzzing issue when I power on, regardless of speakers attached and I've tried numerous outlets and power cables. When switching to "HP" (headphone mode) I do not get the buzzing. When speakers are plugged in, they hum too. Sub hums regardless unless HP is enabled on control unit. Having said that, I hope this post resolves my issue!
I took amp apart by taking out screws along the orange line surrounding the back plate. I then took the unit out, unplugged the sub +/- leads, and examined the board. Attached is a picture of the 100mFd 35v caps referenced in the post, I believe.
Please confirm this is correct and I will proceed going to Radio Shack! I've done soldering before, the space is tight but do-able. Thanks again and I hope it resolves my issue!