Router settings on MoCA network? - eviltoast

Recently installed and got my home MoCA network running (Previous post: https://www.reddit.com/r/HomeNetworking/comments/17zr419/new_moca_network_issues/), which once installed correctly I was getting speeds up to 550 Mbps down (I pay Spectrum for 500 down).

However, right before Thanksgiving, speed dropped to around 90-100 Mbps consistently regardless of time of day or device (both wired and wireless). I figured I had a bad coax cable somewhere and replaced a few, but was still getting this speed.

Had a spectrum tech come out, and together we traced the problem from the tap through the network, and it seems to die off right at the router. The tech suggested I buy a new router but I’m wondering if its just a settings issue. For reference, I have a Netgear Nighthawk R7000. I’ve already logged in and double checked that the firmware is up-to-date.

Other thoughts I’ve had that could be causing the problem:

  1. I recently purchased a VPN subscription to NordVPN but have never used a VPN before, and I’m unsure if I need to change router settings for this.

  2. One of the ethernet ports connects to our solar panels, which only communicate at 100 Mbps, could this be influencing the rest of the network?

  3. Actually is the router itself, and I need to buy a new one. Suggestions?

As always, any help is much appreciated!