I’m having the same problem, I just purchased and installed 4 stick up cam’s (wired) all connect to a TP Link M4 mesh router and the live view doesn’t work (If I restart the unit it works for a couple of hours and then nothing ( when I restart / reinstall the unit it works for a couple of hours and then nothing). I checked the settings and all the devices average RSSI range between 44 to 45. I even moved the router a couple of feet away from each unit and the problem still happens.
I also have the flood light cameras and doorbells and they were perfect no issues at all with the same router.
I guess I’m gonna have to take them down and send them back. Not a happy customer!