etlsport,
engine whine was a problem for me as well... the only real way i found a solution was through a lot of trial and error troubleshooting. in my case it ended up being a bad head unit ground (although, there was still a *slight* hint of noise even after that...)
before buying bandaids like the isolator, make take some time to review all the connections power, ground, etc., (also making sure your RCA's are connected properly - my monster cables are 'directional').
not sure how your wiring is laid out, but also make sure the power wires do not run along side the rca's, etc.
best of luck.
-beeej.
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He lingers -- happily -- in a new hybrid state of semi-hormonal adolescence and responsible self-reliance.
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