Anyone has had this happen to them. My 6 month old Mesa Roadster started making high pitching crackling noise today. So after about 5 mins of this it finally dies out in silence (no power). I check the fuse it's black so obviously needs a new fuse. I then put the new fuse in, but now channels 1,2,3, when switched on slowly dies out into crackling silence. While channel 4 works perfect hmmmmm????????