Hi. I just received a Ashdown Mag 300 head I ordered online from samedaymusic.com. I plugged it in to my SWR cab and fliped it on. I had the input and output knobs turned all the way down. Upon powering it on there was a loud hum/wine sound followed by a couple popping sounds and then silence. Any idea what might have happened? Output transformer fried? This amp was suppose to replace my old head that just died and I need it for a show friday. If it is an easy fix I would keep it and fix it so I could use it friday. If not I guess I'll have to order something and have them overnight it. Thanks.