New 2020 ROKU Dolby Vision. Everytime a video is played on Youtube the Audio starts up to 10 seconds after but is in sync. All other streaming devices work perfectly including a ROKU 4k and TCL TV.
Assuming you have the latest firmware (9.4.1-4208) - Settings/System/System update/Check now
Make sure you have Settings/Audio/HDMI="Auto passthrough" (NOT auto detect, which is default).
Thank you for quick reply!!! Yes, I've tried each setting over and over . All updates applied also. Complete system resets have been done. Input locations of hdmi have been switched. My old 4k box never had this issue.