Engine noise

We havnt Even touched transistors, just mesh current and node voltage so far

 

I just had Best Buy install an Alpine MRP F300 Amp today. I had replaced my speakers a few weeks back (Alpine 6x9s front and Alpine 6.5s in the rear). The amp is a 4 channel and at reasonable and louder volume sounds great. However, at very low/low volume there is a constant humming through the speakers even when the head unit is powered off. I have the stock 6 disc (non- JBL) head unit. There is also some engine noise matched to the engine RPM; however, that is not nearly as annoying as the constant humming noise. Any idea? Any suggestions? I plan to take it back tomorrow, just looking if anyone can give me some pointers so they will not be able to feed me a line. Any help is greatly appreciated.

09 DC TRD

 

An update on my issue - went back to Best Buy today and they were able to correct the issues. They grounded the head unit differently and replaced the line out converter with a different one and it appears to have corrected my issues.

 

No not yet. I am waiting for my new unit to come in. I am getting the Kenwood 9140 installed so I will wait untill then. They had it fixed before but then I upgraded the speakers and amp and then is when the noise came back. I am thinking its a grounding issues. Ill update this as soon as it gets fixed.

Thanks for all the help from everyone....

 

I have a similar problem in my truck. Are you guys sure that running the RCA wire next to the power wire is a myth? Because I get the same problem of hearing my trucks rpm threw my speakers (not loud) but the only thing is the sound is only coming from my drivers side front speaker. Any thoughts? Sorry to bring back an old thread

 

if its only coming front he drivers front speaker you probably have a set of component speakers with a xover externally mounted. its very possible that the xover is sitting next to some electrical wire. since there is a coil inside it it will easily pick up alternator whine.
try relocating it.