The Behinger gear's build quality is veryspotty. I had one supposedly new Composer Pro delivered with the power supply loose in the chassis- that allowed the power transformer's core to contact the chassis, and gave me a righteous hum (both audible, from the transformer vibrating, and signal based, from the line noise getting into the chassis.
If you're not comfortable ripping into your own gear, then take it back to the dealer and have them repair it. Or swap it, in which case they'll just rebox your unit and sell it to someone else, most likely. I think I was about the third owner of that dodgy one I got, because there was some black electrical tape in there in an attempt to keep the transformer from shorting to the case- my other Composer Pro didn't have that.
And no, I didn't buy it as B-stock. Caveat emptor...