RBR750 Restarting Approx. Weekly

I have an RBR750P/RBS750 pair. It seems to spontaniously restart about once a week, which is quite annoying. We didn't have this problem with our older Orbi RBR50, which this system replaced. We purchased it at the end of June from Amazon; of course, it is a few days out of support.  I have made sure that it has the latest firmware V.6.3.8.5_1.4.80, V.6.3.8.5 on the satellite, and I've tried it on different outlets.

Any suggestions. It is where the older Orbi was, and I didn't do a lot of reconfiguration (it is connected to the same cable modem, etc.). I've seen the suggestion of doing a factory reset; haven't tried that yet. I also saw something a few years old about email logging, but I'm not sure about that.

Any ideas? It looks like trying to coordinate a hardware warranty return is a pain, and one would expect Netgear would have something more reliable after so many years.

Thanks,

Daniel