Digital Audio output -auto, pcm or pass though?

[Shell20]

We have a qe95t tv and hw-q70t soundbar.  When digital audio output is set to auto ( the default setting), we have lip sync issues. But at different rates on different channels or programs.  We have Sky q box connected to one connect tv box via hdmi.  And sound bar hdmi earc connected to one connectbox earc hdmi.   I found if I switch digital audio output from auto the lip sync problem is solved.  So my question is

1 is there any advantage to the auto setting at all? And if so any other way to resolve this

2 if not am I best switching to pass through or pcm?  What’s the difference?

3 is it best to connect Sky q to the one connect box or to the sound bar?

im so confused with it all.  We want to use q symphony, which means the sound comes from the tv and the sound bar at the same time.  But then I read about Dolby Atmos etc and not sure if we are achieving this etc

I really wish tv manufacturers would give basic ***** proof instructions stating this is the best setup, but you can do this as next best etc.

any help appreciated

[DaveP2]

I have exactly the same set up with same issues...ahhhhhh.
just get get Symphony Q at all at the moment. Did you get anywhere on the settings to get this to work. very frustrating.

[Shell20]

Unfortunately not. We had to return tv and soundbar as Samsung couldn't sort audio problems we had. ie sound dropping out randomly from 2 mins to hourly cycles. And sound suddenly appearing yo come from underwater or glass or something. only thing that rectified that was to change output, channel then back again. Didnt always work for long though.

[grecianite]

I have the same issue - so annoying after spending loads on a top of the range setup! I've got for PCM with a 20ms delay but still not convince the syncing is spot on!

Hopefully an update will resolve this issue soon!

[adam991]

This is a simple and silly mistake so forgive me im not trying to insult but are you using the TVs actual sound with the soundbar as well? On almost every single set up ive seen you have to completely eliminate the tvs sound and only use soundbar

[Daveyboy123]

Lip sync issue is present for me whether I use receiver or TVs built in speakers or set to auto or pcm

[CB91]

Turn arc off if u have good set up for q symphony, if I turn on eARC with 2.1 ethernets I lose rear and sub sound. 
qe90t and q950t btw. Symphony sucks in my opion I get perfect shaking room and rears / sub keep working. I still get atmos n hdr 4k on appelbox and on samsung hub  

For me 50 works best with lip sync  

 

[Discriminator]

Have Samsung QE55QN700A (2021) Neo QLED HDR 2000 8K and Samsung HW-Q950A Bluetooth Wi-Fi Cinematic Sound Bar with Dolby Atmos, DTS:X, Wireless Subwoofer & Rear Speakers + Sky Q box.   Same issues - lyp synch on live TV via Sky unwatchable - no option to delay video as opposed to audio. Problem solved by choosing PCM - but then you lose 5.1.    Found the answer was to select output as "Pass thru" (if it offers you this option). All sorted and good surround.......but....certain DVDs will not play at all, some are silent ...might be the output settings on my Sony DVD player but a bit odd that some discs will play and some will not.  The guidance from Samsung is appalling and Sky accept no responsibilities for the synch issues using the Sky box. £1800 well spent!