Seems to a problem over which you have no control - - - it's a known problem with Youtube on some TVs. Following article refers to Roku TVs & devices, but other brands could be affected too if it's happening to you:
http
/piunikaweb.com/2018/02/08/youtube-confirms-audio-sync-issue-with-roku-tvs-and-streaming-devices/
I assume Youtube/TV manufacturer are working on trying to fix it so make sure you've got your TV set up to notify you of software updates automatically.