B24 Ethernet Port go bad

Checking to see if anyone else has had a handful of B24’s with the Ethernet port go out. I had heard some time ago that the B5’s or B5-Lite had have that happen but we had to replace 6 B24’s in just over a week. We have them powered through a Netonix switch, with polyphasers in line. Last week we had one go out, then a day later another one went out different switch’s, different parts of our town. Ironically I had just pulled the config off the second one 2 hours before it went out. After setting for a couple hours I was able to log into it again and default it, but shortly after I wasn’t able to get into it as it would power up, but before it would start pinging, I’d see network cable unplugged on my computer and the power light would go red for a couple seconds on the B24. It did that 5 or 6 times before I gave up and caulked it up to being bad. Yesterday I had 4 of 10 go out on same switch at the same time. My theory is a brown out or something along those lines took them out, but we’ve had these up for 5 or so years without issues. We don’t have any UPS’s at our sites, wondering if that would be a good thing to look into to possibly help with a Brown out if that is the case, or is 5 years lifespan something we should look at as far as replacing these links?

After talking to another WISP provider, he pointed out the latest firmware update,, that patches a known issue with the B24 going into a reboot cycle after loosing NTP and getting it back. So far 3 of the 6 B24’s I have been able to get to and update firmware, setting it near window to get GPS and holding strong. Long story short, always read the release notes, and keep your firmware up-to-date.