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I just installed my amp and subs in my truck and I get a humming sound from my speakers when the truck is cranked and the frequencey matches my rpm's. If I give it gas the subs pitch raises. Once my music is playing its not noticable but at idle its annoying. I believe I have everything grounded correctly. Oh yeah, I was thinking of removing the factory isullation from the back of my cab and putting in dynamat; good or bad idea. THanks!

2008 silverado crew cab ltz/ w 5.3
 

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you have the siganl(RCA wires) and the power supply running down the same side. They need to run down opposites sides of the vehicle to keep that from happening.
 

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Just to add, it's not always just power supply that does it. Lower quality cables are more "sensitive" to interference. That can come from any wires next to it. Choices are better RCA cables, or re-route them away from other wires including factory wires. Also, make sure the ground point is good, not just a simple screw. Make sure the terminal is on bare metal (touch up with same color or clear nail polish or spray paint AFTER it's attached to seal), screws suck at being a conductor. Also, most sub amps have a low pass filter that should filter most noise, check to make sure your amps set properly, including the gain.
 

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he could also put in a in-line noise filter to and probably correct this problem. if u do this, sometimes u have to put it betwwen the headunit and the rca cables instead of the amp and the rca cables. this happened to me with my other car. u have to use trial and error. as for dynamat i would only spend that money if ur vehicle is just rattling and vibrating to the point where it is either damaging the truck or is just plain annoying.
 

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he could also put in a in-line noise filter to and probably correct this problem. if u do this, sometimes u have to put it betwwen the headunit and the rca cables instead of the amp and the rca cables. this happened to me with my other car. u have to use trial and error. as for dynamat i would only spend that money if ur vehicle is just rattling and vibrating to the point where it is either damaging the truck or is just plain annoying.
RCA filters are only a band-aid that hide the real issue.:slap: You have what's known as a "ground loop". Make sure all your grounds are good. You want to attach to the most solid body panels or frame possible. (ie floor pan or frame rails) I once had an issue where the headunit did not have a good ground to the RCA outputs and it caused alternator whine. Try touching a wire that's wired to ground to the ring of the RCA connectors. If the noise dissapears, there's your problem.
 

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i never said that was the best solution only a possible solution. a low cost solution in case that is a concern. tracking down his ground issue might be beyond the scope of his mechanical ability or time constraints.:fighting0037:
 

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If you cant find a good ground, or if anyone else in the future is looking for good ground in a pick up, the seat belt bolts have to be bolted into the frame, also i think the seats have the same rule, but im not 100% sure about the seats.
 
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