I have exactly the same red light issue in the main router. Its only downside is that the devices connected to the main router’s other lan ports cannot connect to internet while connections via wifi work just fine. Perhaps connecting also the wan port to the switch fixes everything.
Did you...
I updated the firmware to the latest and started to have issues with WLAN and everything connected to the remote node. Since I had no clue what version did I have prior the update I’m glad I found this thread. Thanks to you all is well with 42095. I’ll contact Asus as well.