Need help with Dolby Digital 5.1 sound lag

[Chamo954]

I recently purchased a Bose Soundbar 500 with the Bass Module (Sub) and Surround speakers, it's a beautiful, loud, sleek system. I have it attached via HDMI Arc to a 2017 Series 5 Samsung TV. I also have my DirecTV box and a PS4, both through HDMI to the TV.
I know that the Soundbar supports Dolby Digital sound, but when I set my TV to 'HDMI Input Audio Format' to 'Bitstream' and the 'Digital Output Audio Format' to 'Dolby Digital' I get a very noticeable sound lag. Even though the Sound Delay option on the TV and the Bose App is set to "0".

The actual Dolby sound I get out of the speakers is beautiful, especially out of my PS4 when I'm playing video games. But the delay of sound is annoying. It happens both with the PS4 and the DirecTV box.
The lag goes away when it set to PCM on the TV and the PS4 but obviously it doesn't sound as good.
I've also tried connecting Optical Audio from the Soundbar to the TV and it still does the same thing.
Anyone know anything about this? Is it an issue with the TV or the Soundbar?
Any advice/suggestions would help. Thanks!!!

 

[lovinthehd]

What happens when you adjust the sound delay to other than 0? Can you only make it worse or can you improve it? Not familiar with your gear, I use an avr which has either an auto sync (or manual sync) to deal with such.

 

[Chamo954]

What happens when you adjust the sound delay to other than 0? Can you only make it worse or can you improve it? Not familiar with your gear, I use an avr which has either an auto sync (or manual sync) to deal with such.

It makes it worse, makes the gap even larger.

 

[Hobbit]

I know that the Soundbar supports Dolby Digital sound, but when I set my TV to 'HDMI Input Audio Format' to 'Bitstream' and the 'Digital Output Audio Format' to 'Dolby Digital' I get a very noticeable sound lag. Even though the Sound Delay option on the TV and the Bose App is set to "0".
!

I'm a little confused on this part. I run all my components to the AVR through HDMI - Blu-ray and Roku. I've never messed with any audio output settings. I just let the AVR decode the signal to what it's being sent. Or, allow it to convert PCM to dolby surround.

Shouldn't the soundbar be able to recognize and decode the input signal? If it's being sent DD (Dolby Digital) it should play it as DD and if it's sent PCM it should convert it to Dolby Surround?

Perhaps all this converting is adding a delay?