Not sure how to describe this but yesterday when I fired up the JP after about 30 seconds the pickup lost a lot of power and sounded like the strings had something on them. I switched pickups same thing a few seconds of good tone then it went to pot. I switched to the piezo same thing. Thinking maybe the battery I tried 3 new 9v batteries. No change. Changed the chord out put same thing. Thinking maybe a effect board defect went directly into the amp. Same thing. Not sure what is going on or where to start trouble shooting.
In short both magnetic and piezo pickups lose volume and sounds like if you push the whammy all the down with the strings against the frets (best description I can think of). It also occurs regardless of which 1/4 inch out put I use.