little bit of whine

[colonel6632]

hey everybody.

i have a quick question... answer may seen obvious but i've already tried fixing it.

i have 2 amps and a crossover in my backseat.
a alpine mrp-m1000 amp for my subs and works fine
and a old clarion 2 channel amp that puts out 75w rms
and a jensen crossover connected to the clarion amp.

so heres my problem. the clarion amp has a small amount of alternator whine. its nothing crazy but it is just a small amount. and is only noticeable and quiet levels. subs don't have any whine

i have the 2g (i think... or maybe 1g) power wire running on the driver side to a distribution block that goes to the amps and crossover.
i have everything grounded to the bolt that holds the backseat in on the drivers side... you know what i'm talking about i think.

i have the rca's for the subs running on the drivers side (i know wrong, you dont run the power and rcas on the same side, i told my friend that when we were installing and he did it anyways, i plan on changing soon enough). i ran the rcas for the front speakers on the passenger side.

i've heard of adding a small capacitor to the power cable of the amp... but i havent done that.

what should i check next?