The question is: What are you guys doing to damage your preamps?? I know you're cleaning them but what specifically did the damage during your cleaning?
I want to make sure I'm particularly attentive to that to prevent doing so myself (may not be relevant to my Insight+ Pre).
You're trying to embarrass me, huh?
Well, "dusting behind" isn't quite correct. To really get in there I was moving the cabinet, not knowing the amp was on (!), knocked the interconnect to the amp off the pre, touching I'm not sure what but probably part of the preamp, thus big bad noise through the speaker.
Frank said that type of thing usually messes up the amp. I'm going to switch my pre's once more before sending to Frank, but I think it's the pre....

Murf