Help with parasound PHP-850 hiss

[Howismydriving]

I purchased a Parasound PHP-850 from Audioadvisor 5 months ago as for a 2nd system. I finally got an amp, and hooked everthing up. The amp is a Adcom GFA-5300. I am also using a Sony es333 CD changer and Epos 3 speakers.
What happened when I hooked up the pre amp is that there is lots of hiss out of the speakers. It is noticable 5 ft from the speakers. I have tried using different interconnects, isolating the pre amp from the rack that the other equipment is hooked resting on, using a different power circuit from my house, different power chords, and using an old Marantz 2250b reciever as a pre/power amp.
When using the Marantz pre, the hissing is to a minimum and can only be heard right with my ear next to the tweeter.
This hiss is there at the same volume and tone using either the direct or cap outs on the pre.
What can be done to minimize this? I have not called Parasound yet, for I have not submitted my warranty card. If I do submit it, will they consider this enough of a problem to have a look at the unit?
I like the sound of the pre, it is very nutral, but even with my 88db speakers the hiss can be annoying.