Hi Scott, you can use the built in Notch Filters in your ToneWoodAmp to 'kill' the feedback. The following is pasted from our Adjusting The Kremona NG-1 Pickup article.
Set Notch Filters:
1. Click here to view an instructional video first.
2. Low filter: Frequency (Parameters Knob) = 261hz*, Cut (Effects Knob) = 20*.
3. High Filter: Frequency = 866hz*, Cut = 18*.
The Above Are Estimated Positions Only. Values May Vary Between Guitars.
Scott Sulzbach