That is still high for a 6th gen. People here run 50 cameras on a 4th gen at half your CPU%. Something else is going on.
12 cameras going thru Asus routers, regardless of whether you have a drop or not is problematic.
Cameras connected to Wifi routers (whether wifi or not) are problematic for surveillance cameras because they are always streaming and passing data. And the data demands go up with motion and then you lose signal. A lost packet and it has to resend. It can bring the whole network down if trying to send cameras through a wifi router. At the very least it can slow down your system.
Unlike Netflix and other streaming services that buffer a movie, these cameras do not buffer up part of the video, so drop outs are frequent. You would be amazed how much streaming services buffer - don't believe me, start watching something and unplug your router and watch how much longer you can watch NetFlix before it freezes - mine goes 45 seconds. Now do the same with a wifi camera and it is fairly instantaneous (within the latency of the stream itself)...
The same issue applies even with the hard-wired cameras trying to send all this non-buffer video stream through a router. Most consumer grade wifi routers are not designed to pass the constant video stream data of cameras, and since they do not buffer, you get these issues. The consumer routers are just not designed for this kind of traffic, even a GB speed router.
Maybe it doesn't happen right away but that doesn't mean it wasn't sitting there waiting to happen. Maybe another device on the wifi starts using more bandwidth, you have Alexa or some other Amazon product and now someone is sipping bandwidth through Amazon Sidewalk, a neighbor is sipping your wifi, or you have an ISP provided wifi and it is acting as a hotspot for other people on their system, or a neighbor added a wifi device and you are not getting interference. Tons of things can cripple the wifi connection, even wifi add ons you don't control like a neighbor.
My camera bandwidth demands are 350Mbps - that will bring any consumer wifi router to a standstill, even a GB router with a lot of RAM.
You need to either get a VLAN like the Edgerouter VLAN switch or a dual NIC system to keep those cameras from passing thru the router OR at the very least connect the cameras and the BI computer to the same switch and then the switch to the router.
Your key of 0.5 is because the iframes are not matching the FPS.
