When I was playing both my Lakland Skyline and my Carvin I noticed this annoying crackling when using both of my amp setups. It was louder thru the big one because of the tweeter. Cheers to Peavey because I didn't notice this problem with my Cirrus - probably because Cirrus pickups are the best ever IMO - off topic. So why is this in the amp forum you ask?! Well when I unpluged my Skyline from my GK MB150 and plugged in my head phones and turned up all the knobs, I could hear the same crackling. The basses make it louder but the sound is still there without any input in my GK. When I touch metal on the bass, the crackling (and hiss) gets quieter too. What do you think? Something funny with my power? I'm going to listen for it at band rehersal and see if it could be the power source. Also, incidently, the line voltage meter on my Furman went out! what's up with that? Its like the bermuda triangle here - my internet dsl only works when it wants to as well.