I have an older RCA plate amp that I had been using for my little sub in my room. I accidentally tripped on the signal cable going to it, and in doing it it pulled the entire amp along the floor, ripping the Speaker wires out of the sub box. (monster cable connector, very strong apparently lol) Now, I get a hum, with very little output from the amp. I put it aside for a while, but today I decided to mess with it. I used a spare HU to feed it a signal, and while it would play, there was a nasty hum. Now, the HU was being run off batteries, no Power supply charging them. The HU is in full working order, but when I touch the ground to the ground of the rca connector, the amp comes to life. No hum, works flawlessly. Here's a vid so you can see exactly what I mean.
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