hi guys, any of you guys know a little technical stuff about amps? i just bought the new Randall vmax head (dual preamp) one tube one solid state and a 300 watt solid state power amp. sometimes i get a weird "electrical storm" kinda effect in my backround hiss that occelates in pitch. also when i change channels sometime i get a little "pop" and will i turn off the amp i get a "crack" out of the speakers. anyone have any ideas? anyone's amp on here do that? its less than a day old and i'm just trying to gather info before returning it. thanks