Squealing/crackling from speakers

[Jaeden de boer]

I recently installed a new alpine head unit and Kenwood speakers into my 1990 1500, after wiring in the head unit and installing the speakers I tested the system and everything worked as it should, the next day I went to mount it and afterwords if I turn the volume up past twelve I get a horrible squeal and crackling sound from all four speakers, I pulled it back out and all my connections are tight, I have good steady voltage at the plug, any ideas on what could cause something like this would be greatly appreciated.

 

[DerekTheGreat]

Check your grounds, clean up where they ground out inside the dash. Not sure where that is off hand but I know the factory amp grounds out using the three bolts which hold it in place to a good extent. Also, the factory speakers are just junk, so if they're still in there, that could be a contributing factor.

 

[Jaeden de boer]

The speakers have been replaced, I ran a second ground for testing to clean peice of metal on the firewall and are squealing/crackling still persists

 

[DerekTheGreat]

You gotta ground the amp section, where did this wire of yours go? The amp section seems to ground directly through the metal bar it mounts to under the dash. I had a bunch of radio noise when I swapped back to a factory radio, and that was the issue.

 

[Jaeden de boer]

I have completely bypassed the factory amplifier since it was not necessary becuase the new headunit has a built in amp, I’ve tried multiple ground points on the truck with no change.