What mattmiller said -great!
But if that doesn't fit it, the amp may require 1 or more fuses to be replaced. Although I don't know of this amp, what you described sounds like a fuse issue.
Always best to send the manufacturer an email about it. See what they can do for you. In some cases, they will pay for replacement parts, take responsibility for servicing it, or both!
Good luck...hope it gets resolved. Malfunctioning amps have a soft place in my heart.