I'd call Crown direct if Musician's Friend won't find a good solution for you. We had a Crown amp go bad a few months ago only a month after it was installed and they express shipped a new one direct before we even took out the bad one. Crown is one of the best in the biz... if anything I bet they could repair it for you.
Oh ya, nice job!
Like thxgoon said, call Crown up. I've spoken to them and they are nice folks. Your XS900 is under warranty for three years from now, so they will set the situation right for free.
If they don't express ship one out like thxgoon said, they'll at least send you a prepaid shipping label/box for you to send the amp in and they'll fix it and return it for no charge as well. I'd do that before paying for a new one.
I'm going to call them tomorrow and see what they can do for me.