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Discussion Starter #1
Hi all,

Have a listen to this(careful, it's quite loud!):

That's what my driver side front door speaker sounded like. It started happening around February and I hadn't driven the car for about four months while deciding whether to get the head gasket replaced(which is what I had done in the end).

I've fiddled with the head unit settings and it's not regular interference. It happens whether the car is stationary or moving, and with the car on or off(by off I mean no key in ignition but radio still functioning). It comes from both the little speaker next to the vent and the larger speaker in the door.

The head unit is the BMW Business Radio(tape/radio, built-in amp, 40-pin with 6 CD changer in boot) and I have a Dension 100 iPod device with the CD changer retention module.


- It's only the one channel doing it. Rear right output is fine*, as are front and rear left outputs.

- It's not radio interference. Although it sounds similar in the recording, it sounds quite different to radio interference in real life.

- I get the sound no matter what mode the head unit is set to(radio/tape/CD). I've tried opening/closing the door to see if it could be a wiring issue but it sounds exactly the same.

- I wiggled the head unit wiring about and it didn't change anything at all. It didn't even alter the crackling sound, which is quite uniform.

- The volume of the crackling itself is exactly the same regardless of what the sound volume, balance and fader are set to - even if there's no sound and the volume is on zero. Also, adjusting the volume doesn't affect the crackling. The crackling is quite loud.

- While I recorded it I kept absolutely still and the car was parked yet it would crackle for around 20 secs then start to go quiet and stop for about 10-20 secs then start again.

- If I switch the head unit off the sound stops. If I switch it off while it's crackling, the crackling resumes when I switch it on again.

- I plugged the head unit directly to the CD changer connector, bypassing the Dension completely in case that was the problem, but it still happens.


* I rewired the Dension loom(leaving the car speaker wiring untouched) so that the rear right channel from the radio feeds both the front and rear right speakers and it's been fine but this morning it's come back! So now it may well be the rear right channel from the radio making the crackling noise as well as the front! Left side is still fine.

I was wondering if anyone's experienced this before? Even if you haven't, just throwing around ideas might help. I really don't feel like buying a new radio but it's looking likely :(

Thanks! :thumbup:
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