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Discussion Starter · #1 ·
I have a tdi, when playing a CD I hear a buzzing interference on the audio ONLY when I accelerate, when I take my foot off it stops. I didnt notice this before as its only noticable at low volumes.

any ideas of how to stop this ?? is it common on tdi cars ??
 

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you have alternator whine..

Is it a OEM system? Do a websearch for alternator whine.. loads of fixes.. things like suppresors on the alternator etc.

Amit
 

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Discussion Starter · #4 ·
yes its standard gamma unit and single CD player, only happens when the CD is playing though.

any quick fixes ? would they fix it under warranty ?
 

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Cappy,

mines not the oem system, when i first installed it there was no problem now it makes the horrible noise[}:)]. I've tried an alternator suppressor, rca gound loop filter and neither made any difference. What should i try now?
 

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direct to the battery.

if you want somewhere closer, remove one of the screws holding the plate that holds down the gear leaver and earth it that with a ring terminal.

Amit
 

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Mk4's have real problems with this... I have had 3 now and all off them whine...

The best solution I have found is to add a line driver into the system between the headunit and amp. It is more of a masking exercise rather than a fix....
 

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Woody try this. Wiring your head unit directly to your battery..

I had a 306 once with aweful noise problems and this cured it.

One other thing, Are all your power/signal lines to your amps separated???
 

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|No they are not. But saying that i have tried using phono leads over the middle of the car and it made no difference what so ever, so it has to be something else. May try wiring the headunit direct to the battery to see if it makes any difference. cheers
 

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Also might be worth turning the Amp gains down slightly to see if it goes away. Do you hear it all the time or only during quiet patches of music.

Might be worth giving us a quick outline of your setup HU amps eq's etc so that we can make further suggestions.
 

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Have tried plugging my minidisc player directly into the amp and no interference, so this eliminates the earthing and power wires? but as said before i've tried a different phono lead and it was still there! I've noticed it is only coming from the front speakers.

My system is as follows -

Alpine mp3 headunit

focal front components

mission freeway amp powering them

Jl audio sub

Phoniex gold amp for the sub
 

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Glad I'm not the only one with this exact problem. I have a similar set-up: Woodstock HU, Fosgate comps in the front, fosgate amp in the boot powering a JL 12W6 sub and the front comps.

The Woodstock HU uses an external pre-out wiring harness the same as the oem units with 2 sets of pre-outs with 1 common ground. I built my own signal cables with expensive twin screened cable and connectors.

I stripped the whole of the interior to lay down the cables ensuring they where well away from any sources of interference or snags.. I'm on my 3rd re-wire now after trying everything in the text books to resolve a major hum/whine/hiss in the system.

Sent the HU back for testing.. came back fine.. they sent out an electrical engineer to have a look.. spent a few hours over looking everything to no avail. He suggested just running the front comps of the HU, which I've been doing for a few months now and it's fine. But this is only a cheat.. the front comps come alive when run through the amp (tried in a different car, works fine)

I recently learnt/read there's something weird with the mk4 grounding.. something about a split ground between front and back chassis??

I've now been redoing the ground connections in the engine bay, HU and amp and checking the resistance through the chassis to find a solution. This weekend will be the final straw!!

Hopefully feed back some useful info soon!
 

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Well I took half the interior out again this weekend to try and solve the noise problem, but with no joy :-[

Well pi55ed off now.. probably book it into an ICE shop to see if they can help.

Woody, did you solve your problem yet??
 

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No, i'm off next week so i guess i will be spending most of the time trying to sort this out. Good luck wih yours, i know i need it!
 

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Cheers, hope you sort yours too.. I not gonna let a few loose wires beat me!

I'm taking this friday off to have another go.. been reading shed loads of posts on other ice forums, they all seem to just end with no solution?? If and when I find the answer I'll post it up!

One thing I haven't tried is seperating the HU power supply from the oem loom, by totally disconnecting the HU and rewiring it using a relay for the ignition and illumination.. that should seperate the whole system from the oem wiring!

I've also sent an email to bluespot.co.uk (who I bought the pre-out lead from) to see if they can shed any light on the problem.

Good luck!

I'll be back!
 
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