Well, this is the second time that all my music is erased after syncing to iTunes. I do "manual music" managment and keep my collection on a external hard drive. Never had issues in iOS 6.x or earlier but now in the iOS7 beta my music is gone from iPhone again for second time and it's tedious to load it back on again and again. I assume it's a beta bug so I won't bother to do it until beta 4 is out. Anyone else experienced this?