JL Audio 1000/1 amp cutting out?

I recently had a 1000/1 and 300/4 amplifiers installed in my 03 jetta gls 1.8t. I upgraded the battery to an Optima red top, and plan on upgrading the alternator from the stock 90 amp. I also had additional ground wire installed from the battery to the chassis. 0 gauge wire is running into the trunk which splits into 4 gauge from a d-block that lead to the amp's. Separate 4 gauge ground wire run from the amps to the chassis and terminate at the same point in the trunk. My speakers consist of 2 diamond audio TDX 12's subwoofers, diamond audio 5 1/4 comps, and 6 1/2 coax running off of the front channel of the 300/4, and a set of 6 1/2 diamond coax in the rear deck on the rear channel. Im using a pioneer deh-p860mp as a source unit. The problem that im having is that for the first week everything was fine, nothing cutting, all frequencies playing normally, then a few days ago, the subs started to cut out. I double checked the power and ground wire going into the 1000/1, ensured a good connection, and reinstalled the amp. It worked for a bit, then started to cut in and out. The odd thing is that i can tap the outside of either amp and the sub's start to play again, almost like it was pressure sensative. At first i thought it was a bad connection, but all seem to be ok. Could this possibly be a bad ground or ground loop, or maybe one of my amps is causing the issue. Initially i thought it was the 1000/1 becuase it reacted to me tapping on the outside of it, but then i later discovered i got the same reaction when i tapped the 300/4, so this leads me to believe a ground issue. Another thing i noticed is that the power led on the 1000/1 turns on/off sometimes when i tap the amp. Any information you could provide would be great, I plan on taking the car back to my installer to look at the wiring, but I figured asking you guys wouldn't be a bad idea either. Thanks in advance.

Sounds like a ground issue to me.