Master volume quits...

So I need to do more digging for details. The first time practicing with my "B" band, the KPA just stopped producing output. Rebooting would bring it back and eventually I moved on to a cable instead of my wireless and that seemed to work. I didnt take notes are anything, it was practice-and go time. I have 2 KPAs so I am not even sure if this is one unit that is doing it or both. They were at different firmware until recently. Now they are both at 1.0.7.
So last night-it happened again. This time it is on the case rig(case because I stuck the sticker from a gibson case that says made in Canada on the kemper so I can tell them apart). I left the other kpa at the band B prac space. I was hooked up to a crate power block, into the back of it, so just using power. I had been using it like this for a week or more without an issue. Last night-it just died. No output. I noticed that the KPA master volume light goes dark when this happens, though the input light still shows input and the tuner works etc-just no output. Frustrating-since band A gets together with a new drummer tonight-so I will have to throw the axe2 in the car, just in case.
Powered off/Powered on, worked for a while-then died. Repeat. So, I took the main out and plugged it into the rear input on a fender gdec, where I normally plug in an MP3 player. Disconnected the crate altogether. I dont like the thing anyway. I left the QSC K8 that I usually have at home at practice, so it was nice to hear some cabs(as opposed to the crate+2x12). No issues after that. Played for almost 2 hours, tweaking cabs, making general noise, and no issues. Anyone seen master output issues like this? I got one unit from Thomann and one from sweetwater-and I don't recall which is which-though I think I marked one. The issue has crossed firmware revisions. Not sure if it is one or both units. The crate wasnt involved the first time around. That was monitor out-rocktron velo300, main out to RCF monitor. After changing to a cable that night, I played for 4 hours with no issue. The wireless wasnt involved with last nights ordeal.
Obviously, I lack any real data or even common hardware thread at this point. Being a new unit, the first time around I was blaming my other gear. Now I am starting to wonder, but I will take better notes going forward. Just wondering if anyone else has seen master output dead-ness types of issues.

Did a system reset in the mix as well, though I forget WHEN I did that, it was part of the process last night. I didn't have both outputs hooked up last night to see if mains worked in "dead" mode. Last time around-it was total dead, nothing to the mains/RCF or magnum/2x12. I was messing with cabs quite a bit and maybe that was part of it. That ALL-DARK mode of the master was a little scary. I've seen some red there lately with some loud cabinets in a patch or two, but all dark...yuck.