Barney Gumble
Well-known Member
I had this issue with a LG BX, Xbox Series X and LG SN7Y. Once setup if I enabled Dolby Atmos on the Xbox it would introduce a significant delay causing sound sync issues. If I switched to Dolby Digital instead it would remove some of the delay. Given the only reason I bought that soundbar was for Atmos sound it was very disappointing.
I have actually found a fix for the issue now though using the HDMI audio extractor below from Feintech.
Amazon product
Note there is a cloned unit on the UK Amazon site which looks very similar but I couldn't confirm if that will work the same.
Amazon product
So the below is how I use this in my system. Note in my case the critical part I almost messed up is that the HDMI cable from Out2 on the device goes to the HDMI IN port on the soundbar and NOT the TV/Arc port on the soundbar. So as far as I can tell this would only work on a soundbar that has pass through capability with a HDMI in and arc out port. Of course it should work with any AV receiver as far as I can see that supports Atmos of course!
View attachment 1696029
So the reason this seems to fix the issue is it ensures there is a earc connection between the LG TV and the audio extractor. The signal received by the extractor then effectively passes through the audio and inserts a "blank" video signal. This then gets passed to the HDMI input port on my soundbar and is encoded according to the format sent and the blank video gets routed to the tv port that is not connected.
I think the delay that is generated is mainly occurring to those using Arc devices (not earc) and it feels like something that likely happens in handshaking that connection across the 3 devices using that format. It feels like it's probably a Xbox issue to me but hard to prove.
Note using this solution I still connect my XSX straight to the TV so still get 120fps, 4:4:4 and VRR, etc, etc. This is the only way I've found to get Dolby Atmos from the Xbox without delay with my current equipment. I tried every conceivable fix prior to this and they made no difference.
HDMI-CEC still works using this method for me so my soundbar volume works on my TV remote and turns on and off with the TV. The only outstanding niggle is when my soundbar turns on it selects the wrong input so not figured out anyway to sort that but I'm happy to press the input select button for the moment and enjoy the good audio. Also it's worth noting if you switch into games/dashboard there is sometimes a moments loss of sound and then it flashes Atmos and sound is back but I think that's a qwerk of the soundbar and the sound doesn't cut out when in use only when first loading into a game or back to dashboard.
The ‘cloned one’ on Amazon UK isnt HDMI 2.1 and can’t passthrough 4K 120Hz and VRR. Presumably why the other is more than twice the price.