Okay, my Baby Blue 2 just showed up. It sounded good for 5 minutes and then it made this farty distorted noise that was about ten times quieter than the level that I was playing at. I figured I lost the tube but on further examination I found that the source of the noise was the stacked pot on the treble part of the preamp. I tried turning it back and forth thinking it was a dirty pot. When I move it back and forth 180 degrees, not rotating, the sound switches back and forth between the "noise" and a true sound. I pulleds the head and looked for a bad solder but its really hard to tell. I would imagine that these are the same pots used on any of their concentric setups like the SM series. Anybody ever seen this?