Feedback from Channel 1 even when guitar volume is down

[scott7d]

I am getting some feedback from the clean channel that builds up slowly and gets loud, even when my guitar volume is completely off. I thought maybe my reverb was too high, but I run all reverb at only 12:00.

The tone is not effected and still sounds awesome. Just that damned feedback.

Any ideas? Again, this even happens when my guitar volume is turned off.