Hi, I received a new Code 25 today. The unit switches on and the display comes on etc but absolutley nothing I have tried can get it to make a sound.... I don't think even I am stupid enough for this so I'm thinking there is a problem with the amp. The only thing I have attempted is to update the firmware but since none of the USB cables I have tried with it seem to work (though they do work on other items) I can't even get it updated. Anyone got any suggestions before I have to send it back?