I've had my spider jam amp for approximately a half a year now but for the past month its been having issues.  When I turn it on it cracks like the computer is starting which is normal but then it starts a constant buzzing.  It is definitly noticeable in a quite room and very bothersome.  After around 3 minutes, without any plugs in or volume on at all the buzzing will gradually grow louder until (And if I am playing it will cut out the guitar) until eventually it starts crackling kind of and then it pops and goes back to buzzing.  It is unplayable now and I desperately need help fixing it.  Money is pretty tight and my dad bought it for me used, I think it should still be within the warranty time but I'm not sure. I've never dropped it, and I've rarely ever transported it except to play with friends.  Thanks for any help you can give me.