I received a replacement amp for my EP500v2 which was previously making a static or "snow" noise with no audio input and didn't really produce bass correctly with an audio input - just the noise. I replaced the old amp with the new one and now it's silent (well, sometimes) for a few moments and then creates a bass/rumble that grows over a period of time - also with no audio input. To me it feels kinda like hearing a train slowly approaching. I've tried different power cables, different circuits, cheater plugs, removing the ground chassis screw etc. with no success. Changing the crossover or trim may change the intensity of the "rumble" but doesn't make it disappear (changing the volume either makes it worse or has no effect). I've tried the 12volt test on the driver itself and that appears to work just fine.
Anybody have ideas/suggestions? Could it be the driver that's actually gone bad (which doesn't make any sense to me)? I've emailed Brent to see what he'd like me to do as well. After spending a lot of time trying to trouble-shoot the first issue and figuring the amp went bad I'm rather at a loss on this.