Velodyne SPL8R - same problem...

The first thing to do is unplug it, then pull the sub out of the cabinet, then pull the amp out of the cabinet. If you can take out the amp w/o taking out the sub, great. If there are any exposed printed circuit boards, look for dust buildup. Sounds like you've got alot of static energy built up in the internal electronics. If you have to disassemble the casing to get to the circuitry, do so, just do it carefully. Look at the boards. If there's alot of dust, get some printed circuit board cleaner.(pcb) cleaner found at Radio Shack. Then spray off the boards and the subs volume control as well as the crossover control. This will Not hurt any electronics.Re-assemble and test. If you still have noise: Take a careful look at the input side of the amps circuits and traces, if you have a magnafying glass it helps. What your looking for is a bad solder joint. You will see all the little dimples on the boards from soldering at factory. When you look at the solder point, look for a circular ring generally midpoint on the solder or right at board level. This can take some time, however, it's free and it's more than likely the problem. To fix a cold solder joint you need a fine point solder gun, just touch the point that is bad and it will re-seal, then test. Plug n Play. Hopefully it's just dust and you don't have bad solder joints. Velodyne makes an awesome product!, very rarely do I see problems with them. If you need some more help with this, post a comment and we can dig further. Hope this helps