I used that same Crutchfield GLI for my Roady XT, and it worked great. Since then, I removed the Roady, and put in the Harman Kardon Drive+Play iPod interface, and it removes the whine with the HK unit, but it also removes ALL of the low frequencies from the audio signal. I have actually removed the GLI from my setup to get the bass back, but this means I have that pesky whine and hiss again. The HK unit has been a bit of a disappointment to me as a result...