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Although it has probably been there since I first installed it, recently I have been noticing that my Phatbox is cleary more susceptible to interference from the engine that the OEM CD changer was. During quieter music, I can hear a feint high-pitched hum which changes note with engine revs.

Is there an easy way to cure this?

I am not an expert by no means, so I am sure someone else can give you better advise, but I am sure you can buy interference suppressors from Halfrauds. I think they go, in-line with the 12V feed.

Yes, the noise is there, but not really intrusive. It sounds, to me, like it's alternator-generated. Whether it's getting in via the power supply line or the signal lines back to the H/U, I'm not sure.

I fitted the PhatBox when the car was about a week old, so I can't really compare with the OEM changer.

A thought - I wonder whether the PB electronics are grounded to the metal case. It might be worth experimenting with tying the 0V line to the chassis.

I agree, sounds like alternator interference. You may be onto something about the grounding. I think the case is aluminum, so the shielding won't be as good as the CD changer. So you just live with your noise?

I do just live with the noise - sometimes I notice it and it niggles, but most of the time it isn't really obvious.

Get a Bosch Motorsport fuel pump fitted or a full Milltek.....any hum on the phatbox is swamped by the noise of fuel pump or exhaust

My kids make more noise than my full Miltek

Still waiting for a positive reply...

I notice it my car also. Mainly if the volume is turned up for poor quality recordings. Oh well....

Apologies for my ignorance on ICE, but what exactly is a Phatbox?

itaggart wrote:Apologies for my ignorance on ICE, but what exactly is a Phatbox?

Basically it's a boot mounted 20gb MP3 player that replace's the CD player and is controlled via the head unit

You could insulate the mounting points of the Phatbox and then fit a suppressor..? Or listen to Metallica 'One' all the time..?

A bit late to this thread but Dippy I also have this on my S3 whereas there was no noise using the inbuilt CD player. Its not something I'm worried about so have left it as-is for a year now.

Looks like we all put up with it then!

This is pissing me off. I have a suppressor but no idea where to put it as the RNSE take an earth from the aerial. How about a seperate heavy earth directly onto the RNSE case?

There is no obvious earthing point....and an additional earth does not work...