i just installed a amp and sub with box in my friends ride and its go some issues. when u first turn on the system it will make like a cracky stadic sound and contine makeing that sound on off on off for about a min then stop till next time u turn it off and on lol. it also makes those sounds when adjusting the gain. another thing is after the system has been on for awhile there is the odd time the bas would change and the sub will have more bas for less then a min then return to normal right after another crackily tone lol. i know for sure i hooked it up right and the sub is a new JBL 10" but the amp he got off of me used and when it was in my car it did nothing like this.
does anyone know whats up with this issue? and how i fix it for him??
thanks in advance!

 

just curious did u put the RCA cabels opposite from the positive battery cabel that runs to the amp. also check for and loose connections. also check the amp to make sure the remote wire the speaker wire or the positive wire on the amp and make sure there isnt and straggling small little loose wires hanging off the terminals on the amp. also let me know what kinda head unit is used and did u run the wire throgh the firewall or along the side by the fender and around the firewall.

 

sounds to me like a couple of possibilities. 1) Worst case, you fried some solder joints on the board during install. 2) If the head unit in his car is different from your car, that could present a problem. Like bad grounds on the RCA leads, things of that nature. Not to dissagree with rally, but wiring routeing doesnt make crackliy noises. Its a whine that usually matches your rpms. The small little loose wires, though, are definatly something to check for. Hope this helps.

 

That's what I would look for