Alesis dm5 broken ? ? ?

[breeeeza]

I just bought an alesis dm5 off ebay and im pretty sure the thing is broken, allthough i dont know much about it yet.
I havnt tried using a trigger pad with it yet (i diddnt get that far) just to see if it worked i tried the 'demo' and nothing comes out of the headphone socket at all and when i plug it into a main amplifier it comes out very quietly and when i try to adjust the volume it makes an awful load noise (loose circuitry sound) and almost blows my head off. I emailed the guy but havnt got any reply yet but im just wondering whether there is something i can do to deffinatly check, i did try with a trigger pad for about a minute and nothing happened but by then i had given up anyway.

Cheers