@Hank21 

- The procedure is always to power cycle the router, always. If I don't touch the router, it is permanently unresponsive. I even have a daily reboot schedule that is missed during the window.

- I have neither Gateway ACL and mDNS settings setup at this time

- There is no recorded CPU/Memory load during this window, the device isnt recording any data, after the fact, there is just a gap in data.
- All my ethernet cables are probably good, the network runs very optimially under normal conditions, just randomly during the nights, the entire router becomes unresponsive. I cannot directly connect to it in any way. It as if the software on the unit isnt even running anymore.

  @Virgo 

I will try. I have previously reset the entire configuration of the network (all devices) to factory, and re-built the network by hand and it gave the same results. I guess I'll report back in a few days to see if anything changes. This has been a long term problem since getting the device 6+ months ago, mainly, i've just been reading so many posts on the internet saying how flakey the software is on these devices, so was waiting for a firmware update, but never posted myself. But recently, its just been happening so much.

  @Retzel Try changing the default DNS in the LAN.

  @Virgo 

The router stopped responding last night and the network became unresponsive again after doing the recommended steps you gave me.

  @Retzel hi I think a RMA is needed for your case. Try to replace it with a new one and let see

  @KimcheeGUN Just a non-managed 24 port TP Link switch with lines that run to individual rooms, i don't think its possible to have a loop.