Terrible Feedback through speaker

Hey guys,

I am running a Stryker 955HP in a Peterbilt 386 and every time I key up I get a terrible screeching through the right speaker above the passenger side door.

The CB is mounted in the center of the cab under the headliner, it has been tuned and peaked and pushes about 60-80 watts. I am using two wilson 2000 trucker cb antennas and the stock coax.

Could replacing the stock coax cable fix this issue? My previous CB in the truck was a Connex 566 pushing 45-50 watts, I never had the screeching issue but the CB was very sensitive picking up flashing rail road lights or traffic lights. One of the reasons I decided to go to the Stryker was the fact it has better built in RF shielding and so far with it, that is one issue I have not had. Part of me thinks this is a grounding issue with the truck... any thoughts or ideas?

*edit* should also mention the antennas are mounted on top of the left and right mirrors in the stock mounts.

 

It only happens when the trucks engine is running. I think I will be best served if I just replace all of the stock coax

 

I knew I should have mentioned that in the first post but I forgot. I am going to try to set it up and run some better after market coax with better shielding and hope that fixes it. I think anything would be better than the stock stuff, I just didn't really want to buy it because the boss man is switching us from these Petes to Internationals soon and I don't know if I can run the same set up. I hate spending cash for the same thing all the time.

Anyway I will try it sometime later tonight or in the morning and let you guys know if that fixes it.