Unfortunately , some of the drivers either cant or havent yet been made fully compliant, so cant use the full tx power they are legally allowed to.
Some things to check
iw reg get
Have you set the country code correctly? If openwrt is operating with parameters that your other devices arent allowed to, youll likely see some issues. Are you using one of thr channels that has the highest allowed tx power? (Look closely, usually some are limited , often having DFS listed besidr). Have you tried changing channels - probably unlikely but might be interference.
uci show | grep disasso
Is disassoc_low_ack=1 ? If so you could experiement with disabling that.
uci set wireless.@wifi-iface.disassoc_low_ack=‘0’
uci show #optionally with grep filter from above
Repeat the set command above for all radios listed.
To change country codes there are 4 entries showing on my system. Modify them in the same way as the low ack setting from above
OpenWrt does not do anything "special" with the "auto" setting. It does not use the radio(s) to scan for possible interference, outside of the DFS requirement in the 5 GHz band. You are almost always better off picking a channel after you do your own "site survey" than letting "auto" pick what is generally the lowest channel in the band.
Yeah, the 80Mhz channel width means that it uses "multiple channels" (specifically 4 channels at once) so some systems report that as a normal channel and then whether the additional channels are above vs below, other systems report the "average" of all the channels.
In my experience unless you have a totally quiet 5Ghz band, you're better off with 40Mhz channels than 80Mhz channels because interference is reduced.