Got a new replacement amp for my EP600, and once hooked up had same ground hum on the rest of the speakers. With my last amp I had to remove the ground screw (phillips) and the sound was dead quiet.

So it appears the new ground screw was somehow over tightened at the factory, because it is completely rounded out. I can't even tell what type of head is on it, but looking at a few of the other ones near, it is either hex or robertson now.

I've tried using various bits of larger size in hoping to grab onto something, no luck.

So my options are a cheater plug I guess, or get one of those reverse drill bits to try and grab onto it and get it out.

M80s VP180 4xM22ow 4xM3ic EP600 2xEP350
AnthemAVM60 Outlaw7700 EmoA500 Epson5040UB SonyUBPX800