UK-POLOS.NET - THE VW Polo Forum

my other half has a fairly decent sound system in her 6n polo consisting of a Pioneer headunit, sub, 2x amps, 6x9s and uprated front components.

we had to change the headunit a while back as there was a bad earth in the unit causing a lot of interference.
we got another Pioneer unit with all the correct outputs and it works fine apart from when you are driving along, the sub will be really quiet and then all of a sudden, it will get so powerful and the volume increases so that the interior mirror will vibrate heavily.
it will do this when travelling at a constant speed so it nothing to do with increasing volume with increasing speed.

i found that one of the wires to the sub wasn't quite screwed on tight enough, in fact it was quite loose, but haven't had a chance to test the stereo as the cars been at the bodyshop since. any chance it could have been this or could it be something more complicated?

any help would be much appreciated!

Could be the amp, my friends had this in his ibiza and it was the amp linked to the sub playing up. So check them out as well just incase.

cool, will do! funnily enough, someone else said that it could be the amp so will have a look when it comes back from the bodyshop!