Filtering alternator whine

I have installed a component amp in an Acura TSX.  Because of the head unit configuration, I needed to use the existing set-up which includes the radio/cd changer and a small, separate amp under it.  The RCAs seem to be getting engine noise interference.  I have cleaned-up the lead dress and have a good ground but there is still a slight whine.  I think the problem is that I am using the old amp to drive a new EQ/preamp.  The layout underdash is such that the RCA's are very close to the old amp.  Moving them would be quite a chore and I was wondering if I could put a grounded shield around or between the bundle to protect them from the proximity of the little amp.

Thanks, Skip

The RCA's are good quality.  The car came with a HU radio/changer combination that feeds the fronts and rears to a small amp located under the HU in the center console.  This amp feeds eight speakers.  I took the front door speaker outs from this amp, ran them through an LOC and into a Clarion preamp/EQ so I could control a separate sub (not yet installed).  Basically, these are the controls I would have if I could replace the stock HU.  In a post here a few weeks ago I was pretty universally told to use the amp to get enough signal to the EQ

The EQ has three sets of RCA outs which I bundled and ran along the center panels into the trunk.  The power wire runs down the passenger side.  Gain and clarity are excellent so I don't think I am overdriving any part of the system.  The EQ is designed to take a speaker level input from stock HUs and this isn't all that different except they are in two separate boxes.  I think the problem is that the layout requires (more-or-less) that the RCAs go under the first amp and actually have to touch it to get out of the console.  The whine is very faint and I have confidence that the ground connection is solid.  What I am considering is wrapping a grounded shield around the RCA bundle for the short distance it is in proximity to the stock amp.

Skip