engine interference 4 channel response amp

[vnsmanual]

Hey everyone ive recently installed a four channel response amp to my stero, 4x100 wrms at 4 ohm.

now when i have the rcas plugged in just channels one and two ie front speakers i get no interfernece.

If i remove these two rcas and plug them into rca inputs for channels 3 and 4 i also get no interference.

If i have both sets plugged in at once i get an engine noise interference.

Ive tried swapping them over and all sorts of stuff, new rca leads, which im now running stringers but theres no differnce.

any ideas?

[wraith]

How are the wires run? Are they running alongside the power wire?

[HCVP]

What type of head unit do you have, and do you actually have 4 speakers that you want to amplify?

Your allready have a sub running, so i'm assuming your head unit has 3 pre-outs?

[vnsmanual]

yeah headunit has three pre outs, its a Clarion CZ509A. Brought it new just under a yr ago.
Im running to sets of splits, so yes four speakers. rcas are ran down opposite side to power cables.

[haydenvx]

are they near ground cable?