Port being disabled

I did, after much back and forth with Synology support, which even went to the developers in Taiwan. Essentially the issue is plugging the MR2200 into the router when the switch is connected to it as well. It causes a loop burst when switching from the wireless backhaul to ethernet. Bear in mind this could be after a power failure type event too. Here's some info from the last support ticket on what they suggest. Hope this helps.

After reviewing your responses, the results of your testing and going over the logs further, it appears that when you have the mesh settings configured to "Auto" then going from a WiFi backhaul to Ethernet when you plug the MR2200ac into the RT2600ac is briefly causing a loop in the network. The burst of packets caused by the loop appears to be what's triggering the protective mechanism on the switch and causing it to shut down the port connected to the Synology router.
The developers indicated that this isn't something that can be resolved/improved from the Synology side as changing the uplink settings isn't what is triggering the loop. They have stated that since setting the uplink type to Ethernet-only prevents this behavior from occurring, then using that setting for the MR2200ac is the recommended workaround.
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Otherwise, if you want to keep using the "Auto" option for the mesh uplink settings to give the mesh environment a little more fault tolerance, the developers have stated that you'll need to look into the switch's configuration to see if there are any settings that will adjust its thresholds for this traffic. The switch's documentation will likely have more details, but anything related to loop protection or flood protection will be what you're likely after. If there are thresholds that you can raise or disable, this should let the switch keep the port up even during the burst of looped packets caused by the MR2200ac connecting to the RT2600ac and switching uplink types automatically.