@Marcel_Haase Have you tried to set a ping to the AP, Switch, and router, to confirm during outage, nothing else goes down? Try another switch port? Switch showing any errors? Like STP errors? edit:...

@DaKings By chance, are you on the newest controller version and firmware version of the 8411? 1.1.0_Build 20230705(Official) ? Changing port speeds is in changelog. If its not there, I would email...

@MR.S I prefer option 138 myself.

@Naldjer If you upgrade your router to the firmware newest version, you will have the option. https://community.tp-link.com/en/business/forum/topic/609302

@DPlus I hate to say it this way... but getting the lowest end AP's usually doesn't come with all the new bells and whistles. Lower prices with lower end chipset/board. I usually shoot for something...

@ScottStar K... It would be nice if you gave us more details on your setup and configs, so we can help you figure it out.