Got a PD 500XHD. Was working great - no complaints. All of a sudden, I heard a pop, and everything sounds "trebly". Patches that sounded great are crap now. I downloaded the last patches. My unit got out of sync one day (when your PC HDEdit is running but board is off). I've done this before so I know what to do. When I downloaded my latest save on the Open Bundle option, it didn't want to load. Once I loaded it, now all the tones seems "way off". Tested through 2 guitars, earphones, speakers, different connections - all the same. Am I missing something?