Just plugged into my MP15 for the first time since Friday’s gig, and I’m noticing a rather strange sizzling when I play on the low strings or sustain a chord. It’s not an over drive with the note though; It’s as the note is fading this sizzling-hissing kinda comes up, but stops if I mute the strings. Seems like it’s related to the signal being pushed through, which makes me think maybe it’s the preamp tubes? The one thing that makes me second guess is that I have a Roland Cube 20 that’s been doing the same thing, a quiet but noticeable hissing sizzle when the guitar plays through it. Unless all 3 speakers are torn (I ran the MP through an extension cab, no change), could it be the power supply in the room?