[aernative]

Just updated the stero of my 97 Audi A4,
fitted 1000Watt Amp, 12" Octane Sub etc... etc...

Ripped out all the old speakers and fitted my own wires to connect new ones....

Upgrade almost completed - problem is when i turn the ignition on or remove the key i get a feedback through the sub.

I am told this is caused by a hidden amplifier that is trigged by the ignition switch.... I need help finding this amp so i can remove it....

Does anyone know where it is - i am told it may be 1 or two very small devices - My model did not feature the larger BOSE amp in the boot (trunk).

Driving me crazy this one....

Aparantly anyone that fits a head unit with higher power (5V) sub outs is likely to have this interfearace problem.

 

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Ok - this was a red herring, turned out that the head unit was faulty... the only amp in the audi without the bose system was attached to the drivers side rear speaker - which i had already ripped out!

The popping sound was the head unit trying to earth through the RCA outputs i am told, as something inside it was fried preventing it from using the correct earth.

If you need to check for this the simple way is to tun the ignition on and off with the RCA plugs plugged in and un-plugged. If you get feedback in both cases you have an amp to remove - Else its a fault in the head unit.