chromecast ultra not connecting w/Ethernet

I stream allot of wwe network stuff it works just fine when I am watching just on the computer. The second i cast it to the tv the voice is choppy and the video is broken. When I cast something through netflix or youtube on the computer it works just fine. I have connected and set up everything wireless from the chromecast then plug in my ethernet cable. First I am not sure if I am connect to wifi or my ethernet Cable. How Can you Tell the difference? Should the ethernet cable be plugged into router or the modem? I have tried it both ways still the same issues. I am going to try another computer and see that works . I am running out of options to try.

Where is the WWE content coming from? Are you essentially mirroring the screen (i.e., using Chrome's cast screen function), or does the WWE page have a dedicated cast icon within the site? I've found that mirroring the screen leads to more choppiness in general, compared to an integrated cast option for the webpage.

Wwe network has no dedicated chromecast icon. Just cast it through Google Chrome.

Can you use the WWE app? They were supposedly going to add Chromecast support: Chromecast Support Finally Coming To WWE Network; Update on Autoplay | WWE Network News

I have not seen the integrated chromecast icon on the application

Hmm -- you might want to email their support people to see if it's hidden somewhere, or if it never got off the ground. There were a bunch of articles about it coming soon in June of 2016, but then it just seems to have disappeared off the radar.