Have to reset my sony bravia with cast

I am usiing LMDE and chrome with a chromecast device. I have web page with embedded iframe:

https://communitychessclub.com/when_gone.php

<iframe src="https://www.youtube.com/embed/3ZTBngX_Jqc" > </iframe>

To cast, I R-click, select Cast and stop; the cast (if any exist). Then I return to the page and click Play TV. That works about 10% of the time. What I do then is turn off the TV, wait a few secends and turn it back on. Then I can cast to thr TV, sort of, …maybe.

Any suggestions?

So stupid of me… The sony bravia has a chromecast built in. So I removed the external hdmi chromecast and now it’s fine!