What's the result of the nvram show ... command on 378.55?
Same values as with the 27E5 (except for the size which differed by a few bytes)
size: 46818 bytes (18718 left)
1:ccode=JP
0:regrev=45
0:ccode=JP
1:regrev=47
I'm back on 27E5 now and did the nvram erase trick from Sanna1967 right as I was rebooting. Unfortunately nothing changed.
I also noticed that in the Tools section, under Sysinfo, the temperature field for the 5ghz wifi band is shown as disabled - however when I hover over the top right green wifi icon, it shows 5G wifi as using channel 34
Just to add on because I said it didn't matter, it's probably worth it to do a factory reset after loading 378.55 before checking that.
Ok let me try again
By the way, is the nvram erase trick the same as factory reset from the GUI ?