Noise in Speakers

I did some searches in the forums here and didn't quite find what I was looking for. Equipment: Blaupunkt Heidelberg Head Unit; Alpine 50w (continuous) 4 channel amp; Rockford Phosgate 6x9s in the rear; Polk Audio door speakers; brand new Street Wire RCAs. All equipment professionally installed. All speakers run off the amp. My car is 2004 Honda Civic, a 2 door coup My problem: sometimes (though not all the time, which makes it tricky) when I hit a bump or shift roughly, I suddenly hear engine whine through both my rear speakers (though I once heard it in my front passenger speaker as well), and also some crackling. Sometimes there is no crackling and only the whine, seemingly when I hit a smaller bump; sometimes there is no extraneous noise at all. Sometimes all extraneous noises cease when I hit another bump, and sometimes (though again not always), taking off the face-plate and putting it back on (in effect resetting the stereo) makes the noise go away. Today when both noises (whine and crackling) came, I had the headlights on, the air conditioning, and the windshield wipers, and the windshield wipers appeared to be lacking power, as if there were a current drain. This latter fact may or may not have anything to do with stereo noise, but because it happend concurrently (no pun intended), I am assuming there is some relation. The head unit is about a year and a half old with no previous problems; the amp is fairly new and it worked for about a month before any of these problems started. I did have an RCA cable go bad, which is why my Street Wires are brand new--and of course I was hoping that the bad RCA was the problem with the noises, which occurred with the old wires as well, though the noise only came out of the driver's side, rear speaker. I've also had 2 different 4 channel Profile amps (with about the same wattage) malfunction in my car, though with a different problem (according to their company, my particular model had a design defect, which made it function as if it had a power drain: the sound would go way down when I hit a bump or would shift a bit roughly). I mention the other amps in case this information is pertinent. I've been dealing with this mess for about 6 months and don't know what else to do. I don't quite trust the folks who installed the system to do a full system check, and I don't have the tools (or know-how) to do it myself. What could possibly be wrong? Bad ground wire? Loose power wire? The RCAs and power wire appear to be installed on separate sides of the car, so I wouldn't think that were the problem. When and if I do take it somewhere to get the system checked, I'd like some good leads (again, no pun intended) so that they don't try to sell me a new amp and/or head unit. Thanks for any help.    

Sounds to me like something has come loose.  Could be any of your wires including speaker wires or even HU wiring harness in the dash.  Or it could be a pinched RCA cable... Sounds like it's time to remove everything and go over it wire by wire.  Sorry, that is a time consuming process.Support the12volt.com

Thanks for the reply. I was afraid this would be the case.