I'm having a problem trying to use my Pod X3 Live in the effects loop on my Mesa Boogie Roadster. This is a new rig so I haven't gotten it to work properly before. I'm hearing a humming noise, and really need to turn my volume very high to just barely hear my playing at all. What little I can hear sounds lightly distorted and with no effects. On the Roadster: The Effects Loop switch for my channel is turned on, and the blue light for Effects Loop on the front panel comes on. The Loop System In switch is on and the Send Level is set to noon. My guitar is plugged into the Input jack on the front of the Roadster, and the POD is plugged into the Effects Loop with a cable going from Roadster FX Send to the Pod's FX Send, and from the POD FX Return to Roadster FX Return. On the POD: The only "blocks" turned on in the POD's screen are the Loop, Delay, and Reverb blocks, with the effects placed after Loop. The Master Volume on the POD is turned all the way up. It is set to Stack Power Amp mode, but I have tried the other modes as well in the Output screen. What is causing my sound to disappear and how do I fix it?