Just stumbled upon this thread when reading ==>
https://www.snbforums.com/threads/w...rks-being-disabled-something-is-broken.41557/
FWIW, last week and ~12 hours after updating from 380.68_2 to 380.68_4 on my RT-AC88U my 5 Ghz radio started 'dropping out', too.
At first I figured the upgrade to 380.68_4 was to blame. So I flashed back to 380.68_2. Still the issue persisted with the 5 Ghz radio intermittently 'dropping'. Power down the RT-AC88U, unplugged. Waited. Plugged the router back 'in', power on, after a short time 5 Ghz radio still 'dropping'. At that point I pondered doing a factory reset and starting anew...
But then as a last resort before doing a 'factory reset'... I clicked on the 5 Ghz Wireless-Professional tab, set the 'Enable Radio' _radio_button_ to 'Off', click 'Apply'. Then reset the 5 Ghz 'Enable Radio' to 'On' and 'Apply' again. Rebooted. After that the 5 Ghz radio seemed stable once again.
Finallly, flashed again to 380.68_4, reboot once more. As of today, the RT-AC88U has been 'up' now for '3 days 17 hours 55 minute(s)...' with _no_further_issues_ with the 5 Ghz radio (knocking on wood).
As already typed, fwiw.
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