I can generally trouble shoot my own problems but figured I would ask since I had not seen this exactly. A few weeks ago I noticed a thumping through the sub like a bad ground. As I turn the HU down the noise stays constant. So I figured that my amp was going out. But then I noticed that the noise was not present as I flipped to other sources such as tuner or changer. So it's the CD player. But then it seemed to come and go so I start thinking bad ground again. A quick check does not reveal any rubbed wires. It appears that the noise is related to the actual movement of the laser (start disc, roll over beginning to end). The only thing I can think of is a failure in the CD specific portion of the HU. Does this sound right? Could it just be dirty (like I could be that lucky)? I just hate to think that it's going to be ruined like that by noise, not outright failure. Any ideas are appreciated before I start looking for a replacement.
Usually if thery are dirty they wont play discs, I have never heard of a cd player making thumping sounds just on the bass considering it plays all frequencies. Are you sure there are no funky sounds coming from the front speakers? Unplug the bass amp and listen to the front speakers alone.
I had the exact same problem with my pioneer deh7700 first the thumping would only be when i played cds, then after a week or so it went to the radio side and the aux input, so i grounded the chassis of the deck to my car and it went away completely. Then a while later it came back slowly and ended up frying a nice hifonics amp i have. I beleive a ground burnt off inside the deck somewhere and was sending voltage spikes through the rcas to my amps. I changed decks and it went away and has been fine since.
I guess it's time to start checking wires. I like to think my wiring is clean and well protected but even the best need maintenance. I will start checking wires this weekend. At least it doesn't sound like the CD unit specific. That's what I was hoping for. I'll try to let you guys know what I end up finding.
I was trying to explain it was the deck at fault, causing the thumping. I redid my wiring and it helped for a little while but came back again. The thumping didn't go away until i changed decks. So it is your deck causing the noise, it is faulty. Sorry i know it's hard to tell what people are trying to say sometimes, especially me i noticed lol.
I got you, just too many different thoughts to put into a short reply. I am now assuming a bad ground which I am hoping to find in the harness. I understand your broken ground was inside the deck, that sucks. Hopefully mine is just a worn crimp or the original truck wiring rotted. We'll cross ours fingers and see.
cool, i wouldn't play your system when it's doing that, i beleive my deck fried one of my amps. Good luck
And the winner is-a bad wire, probably ground. Just pulling the HU out stopped the problem before my first test so I couldn't really find out which wire. I switched the RCAs to the other outputs but it was already gone. So my "good" wiring jobs just needs to be spruced up. When I have time I will pull the harness and probably redo all connections just for safety. I did not realize how much noise that was throwing into the system and I am lucky I didn't do anything to the amp as the HU must have been grounding through the RCAs and the only reason the radio was OK was grounding through the antenna. IDK but it sounds so nice now that it is fixed. This is a real eye opener to what issues grounding can cause. My changer had quit running (clarion off of HU, no external power) and I figured it was dead. Would switch disk and count tracks but not play. I guess the weak/bad ground was not allowing it enough power to spin because it works perfectly fine now. Thanks for the suggestions and I'm glad I asked. I was seriously thinking of looking for the cheapest replacement.
Good news! lol i'm glad you didn't go buy a deck first, i thought for sure it was the same problem i had. I did think later on it could have been a pinched or grounded speaker wire too to cause a thumping like that.
I see theres been alot of replies but i know what your problem is. Im going to assume this is a pioneer headunit. I just dealt with this problem and its already widely known.. There is a faulty internal ground on the RCAs which causes this noise.. There is a simple fix to it if you know what your doing when it comes to taking HU's apart but its a bit risky.. You can send it back and theyll give you a new one or fix it but the same problem will come back after time!
