The linear PCM is lossless over HDMI and should be the best option in theory. DTS is compressed or 'lossy', but allows the receiver/soundbar to do the decoding. I don't know if the soundbar will display the type of signal if it didn't decompress it. May have to play with that on my setup soon.
For Blu-ray, you may want to use Bitstream. This setting is only accessible while you are watching a Blu-ray/DVD and is found by pushing the "Options" button and looking under audio.
Play around with it. In the end, go with what sounds best to you. You may not find a huge difference in general perception anyway.
Sony XBR-65X900F // Sony HTZ9F Sound Bar & SAZ9R Speakers // Xbox One X & PS4 Pro
Last edited by Coercion Shaman; 05-08-2019 at 05:21 AM.