This just happened to my unit.  I can't believe Line 6 would allow such a nasty bug in their hardware.  I had to reset my unit which wiped out ALL my patches.  There are months worth of patches that are now GONE because of this.  What I thought I had backed up via HD Edit a couple weeks ago was not my User Setlist. One night it works, the next it doesn't.  Line 6, please fix this buzz kill.

Whilst I have never had any crashes that have necessitated a reflash, it does strike me that the firmware is a little sensitive (I was going to say flaky, but that may sound a little more negative than I intend). In the few months I have owned my unit I have had several locks, unexplained reboots, or failures to indentify the hardware via edit.

These have all been resolved in seconds, or merely required a power cycle. (And I should clarify that while I have not felt a reflash / reset was necessary, this has been performed after the firmware update, but I have the same number of ocassional glitches).

I also feel it is most likely related to the USB hook up (my 500 is permenantly attatched to my PC). Still, even though these issues may not manifest in 'standalone' mode, I consider myself lucky I do not gig as I would be a little paranoid.

I follow the forums quite diligently, so I can only imagine that I am in the minority, as few people seem to complain about this type of thing much. That said, on reflection, so many people seem to be very familiar with the reset procedure, I wonder whether its just an accepted part of HD ownership?

I have recently obtained a used, and pretty old non line 6 device that is a similar style of unit, and had no such issues, so from my perspective it is a little bit of a negative against an otherwise great unit.