New Sunfire Theater Grand install help needed

I just purchased a Sunfire Theater Grand (200 x 5) amp, used here on Audiogon. I am currently using my HK DPR-2005 receiver as a pre-pro. Last night, I hooked up the amp to the receiver using interconnects from the preout of the HK to the Sunfire. I hooked up all of the speakers, and pulled out the Avia setup disc to calibrate. Left, center and right all worked fine, but neither of the surrounds put out any sounds. I checked my connections, and I set them up the same way I did my fronts.

I then disconnected just the surrounds, and hooked them back up to the receiver. Once again they worked fine. Since, I wanted to listen how the amp sounds, I figured I would temporarily use the amp for the L/C/R and keep the surrounds hooked up to the receiver. I went to use Avia to calibrate the subwoofer, and the left front was now not working, while the center and right were fine. I powered everything down, and turned it back on, and now all three fronts speakers played fine through the Avia setup disc.

I played some music and movie scenes, and everything sounded great.

Any thought on my problems? What paths should I go down to troubleshoot?

Thanks
Greg