...Also check the fused distibutor you have attached to the back of your sub box. Remove it, then check on the bottom to see if the plastic around the screws is bubbling up. If it is, then you would need to replace it. The vibration from the bass can cause the fuses to move or the screws to come loose within the holder creating sparks and, as a result, heat. That heat causes the plastic to "boil" and "melt" thereby affecting the power connection to the amp creating intermittent operation. I have experienced this before.