Thanks
@Leesureone , I have 2 identical Nuc8 both running OC 6.4 and both connected using ethernet wire cable to the same network, one is running the latest version of Catalina, it sends video to my AppleTV, smart TVs, and sound to my soundBar and speakers perfectly well, also on the sound menu on top bar, all my airplays devices (apple TVs, smart TVs, Sound Bars, and speakers), appears well. On the other NUC8 I have Big Sur and I can not send my screen to my apple TV and I can not send sound to all the Airplays devices that my other NUC on the same network sees, I think Big Sur, broke something, I also have a real iMac running the same version of Big Sur and it sees everything well.