AC68 with multiple bridge devices kills wifi

[Softail]

I was able to segment my wired network into vlans with no problem. When I bring up the vlan interface with an address it works fine. If I create an new bridge device, add the vlan to it and bring up the bridge with the same address, the wifi connection gets weird. 50% loos of pings, not really usable. The wired remains OK though.

I was trying to move the SSIDs onto the new bridges and it seemingly worked OK but didn't function.t Even stripped to just a new vlain in a new bridge, without touching the radios, it already fails somehow. I don't understand how it's even possible for this to affect only the wifi or else I don't understand the bridge devices.

 

[Softail]

Part of the problem with the wifi was that spanning tree was enabled on the N66 router the AC68 access point talks to. Once I turned that off it behaves much more deterministicly. The bridge devices seem to function as expected on the N66. When I use only vlan8 on the AC68 the DHCP request goes out on vlan8/br8 on the N66 and everything works. When I put the vlan8 in a bridge br8 on the AC68 the DHCP seems to go to the default vlan1/br0 on the N66, which doesn't work because it gives out an address that can't be routed on vlan8.

My working hypothesis is that the AC68 bridge devices are losing the vlan tags or are incompatible with vlans in some other way. I've spent way too much time on this already and that's something I'm not going to fix myself so unless something turns up I'm going to give up on this hardware.