MBox problem..no I/O sound at all

I recently purchased the MBox...cool. I hooked it up and fired off a 5.1 session and played it and listened to it, a coule of different times. Now, about a week later, I start up a new session to lay down some new ideas and everything is hooked up ready to go, I record enable track 1, and no signal. I hear the guitar through the headphones while playing it so I know the signal is at least going through it, and I can hear it also through the monitors. So I decide to quit the session and fire off the other session that I listened to a week ago...it plays but no audio. It's like my MBox died. I've tried everything. Any help would be much appreciated. Maybe my box is bad and should exchange it. HELP

hello, when i received my mbox i had some sort of problem. in the i/o setup menu i had to 'activate' the inputs. not really activate, but i clicked on them severall times and after that my problem was over. maybe it;s a bug ? gretings, tantejo.

How do you have your speakers hooked up to the MBox? Do you have a master fader in your session.. and if so, is there any metering post fader on the master fader? Where do you have the Input/playback knob dialed to? Rail