Subwoofer won't play at low volumes.
 

Hi, my subwoofer has not output when I have my stereo at low volumes, it sounds fine when I turn it up, but will cut in and out if I turn the volume down. Please help!!,

You likely have a break in the coil...only with enough power flowing will it get going.

Could it be a bad rca jack in the amp? I have to wiggle it around a little to get the sub to play.

You can try a different RCA to see if that's the culprit. Before doing that, try pressing down on the woofer cone with a little pressure when you find that it's not playing...and see if it kicks in. This will tell you whether the coil has a break in it or not.