Amp Problems
 

I currently bought a Boss Audio R1004 4-channel amp brand new and i installed it on my Pioneer DEH-p3200ub, i ran all the speakers positve and negative to the 4 channels on the amp. i speaker per channel nothing more. I then ran the rca cables to the back of the radio, after installing all the stuff for the amp i then turned on the radio, and all the speakers sounded great. i left it on for at least 5 minutes and after that i shut it off. everything worked great, i then started my vehicle up and then it made a light popping kind of sound from the front speakers and they stopped playing, so i checked all of my wiring and it was all good, but channel 1 and 2 on my amp do not work. channel 3 and 4 do though however. i checked the speakers and they work went hooked up to channel 3 and 4 but not 1 and 2. what could this problem be? i need help this is so frustrating!!

When you checked the front speakers, you just changed the terminals they were wired to on the amp?
I'd suggest you also take the FRONT RCA outputs from the head-unit, and switch them into where the REAR output was plugged in. This will eliminate the possibility that the FRONT output from the deck isn't the issue - when you do this, your rear speakers should start to play (assuming you've wired them back to the original terminals).

Also make sure you havent fade off the front speakers unknowingly.

Check that you havent damaged the RCA's when you pulled them out from the amp when you were troubleshooting. Some people will pull the RCA out from the amp by the cable portion of the RCA and do damage to the cable. If this is the case always pull the RCA out by the head of the RCA. Hopefully this makes sense.

Start checking fuses and make sure all grounds are tight (may be what have popped the fuse in the first place)

I checked both RCA cables and the both work fine. Since the front speakers which are on channel 1&2 stopped working I decided to see if putting one of the front speakers on channel 3 (which channel 3&4 work and they are the rear speakers) so i put one front speaker on channel 3 and moved the rear speaker that was on 3 to channel 1, after doing this only channel 4 played music. The front speakers won't work on any of the channels and the rear speakers will only work on 3&4. So I ran a new speaker with new wire straight to all of the channels one at a time and only 3&4 worked. This is really confusing me, I even switched the RCA cables around reach time i did this and the front ones still won't world

Seems like a problem with the front speakers/wiring which could have possibly damage ch 1&2 on the amp.

Check and see if the speaker terminal of the front speakers are grounding out, that will cause you to have no output through the front speakers.

I'm going to re-wire the front speakers all the way out to the amp and see if that works, maybe they are grounded out and I can't see it. Will 16 gauge wire be good enough to use for the speaker wire?

16 will be fine