Do you have any video during the boot process from the Azbox ? If so , try loading an earlier ( like 2880 ) firmware, that didn't support hardware acceleration, from a usb stick. Alternatively, if it has video during boot, let it stop on the usb stick, and reformat the application area, and reload the existing firmware from the stick.
Try hooking up a TV to the composite video output ( yellow plug ), and see if that is active.
A few things to try, not necessarily in order , either.