I have a new Samsung NEO 8k tv and connected a new Arc to it using the HDMI/Arc port. The audio works but is several milliseconds behind the video. I’ve noticed that I can use the Sonos software to delay the audio which, as expected, makes matters worse. The tv also seems to have a digital audio delay - a slider bar that defaults to 100. There is nothing available in the tv documentation saying what the 100 is or whether sliding it left or right increases the delay. I have tried moving the slider to both extremes and honestly saw no noticeable difference. 
 

I have seen numerous articles about different audio formats that can be processed faster, but let’s face it, we pay a premium for the arc to get Dolby Atmos sound.  I also read an article suggesting different HDMI cables can make a difference  I will give that a try but not sure I am buying that one.

Has anyone experienced this and can suggest a fix?  Thanks!