ok i just put a new amp sub and headunit into my 2000 mustang... the speaker does hit a little u can barly tell it... its 1 12' l5 and a 1600 watt amp... the power light comes on the amp... when i turn it up a little the power hit starts blinking when the subs hit like it isnt getting enough power... i kno everything in this system works... i had another system in there and it did the same thing... changed power wire to 2g and still dosnt work changed RCA cables there walmart brand maybe i said get some better ones... also tryed grounding to a different spot... i think i got the mach 460 system i cant seem to find the amps tho... i dont have a fuse on my power wire and just have the wire wraped around the battary termal... let me kno somthing...