Harman Kardon Subwoofers 'popping'

[SportZ114]

I have factory Harman Kardon audio with the Premium Package. The problem originally existed as the rear speakers/woofers making a loud 'pop' when turning on the car. After a while of living with that all the speakers in the car failed. I replaced the corroded amp in the trunk and everything worked again. Then about 1 month later, I go to back out of my driveway and as soon as I move I hear a loud pop/thump from the rear speakers. I continue backing up and as I move faster the popping speeds up as well. THE POPPING IS DIRECTLY PROPORTIONAL TO THE CAR'S MOVEMENT... BUT NOT THE RPM's. The faster it's moving, the faster the pops. Even with the radio off, they are doing it. And both. Anyone have any ideas/input?

It's strange to me that the speakers pop according to the cars movement... It seems like a short or crossed wires or something but what would make the speakers react to movement (when the car is on of course).

[bms72586]

bad ground some where with the amp, i never had speakers pop tho. i have only heard of the engine RPM's buzzing in the subs.

[bmwill831]

I have the exact same issue except my car is still in the beginning stages, I get the occasional pop from the sub when i first start the car

[SportZ114]

I still haven't found the problem. Someone with Audio background should be able to help, please!!!

The car has to be RUNNING and MOVING for the subs to be POPPING. They pop faster as the car moves faster. The pop is kind of a deep thump.

I've been driving with my subs unplugged for the last 2 months!

[danewilson77]

Me no have audio background or else I would help. It almost sounds like you have a ground or something.

[Derbo]

i gotta bring this back up cause I have the same exact problem

[Draw415]

+1 on the bad ground. If the popping sound speeds up as you accelerate, sounds like it's picking up sound interference usually associated with the alternator. Check all the grounds on your head unit, amp and speakers. There is likely a bad connection in there somewhere.

[kpro]

Interference, bad ground.

[Keebsci]

Do you have good fm radio frequency?

[bion]

I hate to beat a dead horse or dead thread in this case. im having EXACT same problem. i though the speakers were blown. sitting in driveway the sub sounds good at loud volume. then i get on the road. once im in 2nd or 3rd gear the popping is on every bass note. How do i find the ground problem? i have a 2000 M roadster with CD53 radio stock HK single amp and stock HK dual subs. my car was manufactured 4/99 so i have the crap subs. im not an audiophile and they work fine for me except the incessant popping. im getting ready to leave for a roadtrip in 1 day and im going to have to disconnect the subs unless someone can chime in and help on a 1 year old dead thread
I cant find any other info besides this only thread and OP was/is having same problem as me....

[Derbo]

I found out I had a corroded plug to the amp. The copper pins were all green. Clean up the connections and no more problem for me anymore! Definitely a bad connection/ground

[uroe46]

Do you have good fm radio frequency?

Keebsci, What lights are those --NICE! (sorry to interrupt on the radio problems)

[latelife46]

Hi folks - I'm a super-newbie but I am tracking this issue down and will beat it. Here's my experience so far, FWIW...I can truly find no pattern to the popping but at various times have thought it to be: only while the car is in motion (not so), only during acceleration (not so), only during braking (not so), only speed-proportional (not so), only on rainy days (not so)...that's part of why it's so confounding- just when I have it, it does something different.
Here's the two things I do know: 1) it only happens when the ignition is on (position 1 or 2) and only when my driver side sub is connected (take off the wire harness and problem goes away). An electronics person has suggested it might be a capacitor dumping and I think we've all suspected something ground-related. I have also seen where people have experienced subwoofer system failures as a result of components separating from the PC board of the sub amp due to bass vibration and road vibration. Both the printed circuit theory and the ground theory seem possible to me since both would be affected by motion (accel/ braking), rough roads (and speed), moisture...all of which I've seen.
Here's what I am doing:
1) I'm going to take apart the sub amp (there's a video on your tube and see if anything is loose/ disconnected/ burnt-out. If so, it can only be on one channel as the passenger side works fine.
2) If the amp is good, replace the subwoofer speaker.

Before even I do all that I will see if I can swap the channels. I don't think the wiring harness will reach but maybe I can rig something up. If I change the channel the popping is in I'd say it was the amp.

BTW - I also have noticed that my alarm system was affected: With the offending sub plugged in, the alarm will go off whenever it feel like it. With the plug out, no problem - anyone else notice this? Any idea why? - maybe that would help solve the mystery!