Two issues here:
We have a few Force 300 25 units that during the evening will reboot almost continuously. As soon as they associate to the AP they reboot, associate again, and reboot. Every now and then they will associate just fine and stay for a while. Here's the kicker - it only happens in the evening.
Both SMs are served from the same sector. One is has a good connection and one is fairly poor. It almost seems to be a noise-related issue, but the SMs won't stay up long enough to run the SA. Once the SM is up when this phenomenon is happening, passing any traffic over them (like logging into the web ui) will reboot them. SSH will work usually without triggering the reboot.
Both units are powered from a Mikrotik POE out port, just like the other 32 SMs on this sector that don't exhibit the problem. This is not a power problem. Both affected units' mikrotik routers are fine and other wireless equipment we have on site at each location is fine. I have swapped both Force 300 units for UBNT AC powerbeams and the problem goes away. When the Force 300 radios are put back, the problem returns.
During the day, both SMs operate normally and don't have any problems. This problem is only exhibited in the evenings. It does not seem to directly correlate with high traffic on the AP.
There is another Cambium operator that has reported what sounds like a similar set of problems on Facebook and Cambium support has been able to SSH into his radios and tickle something to make the issue go away. Unfortunately, I cannot submit support tickets as I receive the following error each time I try. Any ideas?