Problems with XR500

I'm using a cable modem from Spectrum, and measure consistently 12mb/s on upload and ~480mb/s on the download side.  Model E31T2V1.

I've had the EX8000 about 40 feet away, on a second floor.  Last night, I moved it to the front of the house, on the same level, and about 30 feet away (2 walls).

The channels are set to Auto, and 2.4 is using channel 9, while the 5.0 is using channels 153 (shows as 149 + 153(p) + 157 + 161).

Logging into my router, I see that the R-app for the dashboard is now no longer running (lower left one), with a spinning wait icon and eventually the message "the operation is taking longer than expected. Please briefly wait before using the R-App".  Same thing for the device manager.  They were both working fine last night and this morning.  This is usually a warning sign that the router is no longer going to be working correctly.

2 wifi neighbors, but further off (-72dbm (ch 1 & 36) and -95dbm (ch 5)).  My 5.0 shows up at -45dbm, and the same for 2.4Ghz.

Thanks.