Nope, that's weird. Hiss and hum happen with tube amps but that sounds strange. What's it plugged into? Try plugging it into a surge protector before doing anything drastic. The tubes could be old too, especially if it was a floor model or something. Try tapping some of your preamp tubes with a pencil eraser. If they make a thump they've gone bad.
Winner of the 2011 Virginia Guitar Festival

Protools HD
Lynx Aurora 16/HD192
Mojave, Sennheiser, AKG, EV etc mics
Focusrite ISA828 pres
Waves Mercury
Random Rack Gear

65 Deluxe Reverb
American Standard Strat
Taylor 712
Not to worry. Spoke to the shop and they agreed to just swap it for another. Problem sorted Thanks guys.