I think I have been running my ac15 too bright...For years. Last night I was using it after a bit of a honeymoon with my marshall origin and I couldn't get over how noisy it was. Like pretty high noise floor, lots of hiss. It has been bugging me all day today. I felt like something was wrong with it. So when I got home after work I fired her up and got to tweaking. I noticed the normal channel had a lot less noise than the top boost channel. I like both channels but lean towards the top boost for the added eq section. I ended up cutting the treble way back and turning the tone cut a little darker than I normally do. Initially i was hesitant to mess with my tone. However, not only does the amp have a better, warmer sound now, but the noise floor is vastly reduced. I can't believe it took me so long to realize how bright my tone was. Literally years. Got to thinking, and I know how you dial in your amp is relative to the room you are in, but I just wondered how you other ac15 owners run your amp? Anyone else have a similar experience?