Audio system shutting down

I just finished installing my audio into my '84 this past week. However, I noticed that when I've got it playing and I either turn on the lights, lower the windows or use the push button to open the hatch , the HU and amp will shut off for like 2 seconds and come back up.

Would this be due to my alternator? The '84 has a newer style alt (87-93) and everything else works fine and does not shut off. If non of the above is done..just have the system playing...it will never shut down. I put a light tester on the remote wire that goes into the radio and noticed that the power gets cut to it.

Anyone have ideas on what i should do? I have the following:

Autotek SX4160

The subs are wired in parallel and bridged to the amp for a 2 ohm load. I'm sure the amp won't take that ohm load bridged as it max is 320x2@4ohms. Would my fault be becuase i'm putting TOO much of a load on that amp? not being able to handle 2ohms? I can imagine that would cause the amp to cut off...but not the radio.

Any ideas?

I've been wanting to upgrade to the new 130AMP alternator found on the '94/'95GT's...so i'm gonna do that. Will it also be wise to upgrade the wiring that goes from the alternator to the battery? It is still using the stock 10-12AWG? wire. I've heard some talk about upgrading this wire..but what would be best to use? 8AWG? leave it alone?

I'm gonna upgrade the alternator and just get a nice optima battery at the same time. I'll find out if this helps it and maybe get a cap for the amp because I do see the lights dim when the bass hits. Ofcourse, when on low volume, everything works perfectly.