It's probably one of 3 things..

Bad ground
Amp can't handle that output that the sub is asking for
Sub can't take the power from the amp

 

Who knows, i ripped some wires apart this morning when loading my trunk. Reconnected them all and it doesn't seem to have made a difference. When it gets warmer out i'll have to look into it more.

 

Have your headlights been dimming when the bass hits? If so, it could simply be that the battery is not able to supply the current required for loud bass...

If not that, I would look closely at the amp not being up to the task.

 

Nope, no dimming issues. Haven't noticed any problems since i reconnected some wiring i ripped apart a while back.

 

If you do start noticing problems again, in all likelihood it's probably something like your amp can't handle it or poor wiring. Have you checked how hot the amp gets after the problem happens? Where have you set the crossovers on the amp and what kind of amp is it? Tried swapping phase?

You may just want to check and re-check your wiring yet again. If it was poor before, there might be other hazards elsewhere along the installation. Hope you don't have anymore problems.