Not sure whether to post this to here or !PS5@lemmy.world, so I'll just start with here then cross post if that's a thing Lemmy can do.

So my fiancée brought over some old Battlestar Galactica blu-rays. This one basically. And it seems to only output in stereo 2.0 LCPM. The only suggestion I've seen is to change the settings in the Blu-ray Audio Output menu to either PCM or Bitstream, but I've done that and nothing has changed. Also changed it in the normal settings menu to AV Amplifier and LPCM or Dolby, and neither has done anything. Now, it is being output through a soundbar that doesn't accept DTS or DTS:HD (the Bose 600), which is fine that it changes to PCM, but you think it would at least change to PCM 5.1 instead of stereo PCM 2.0.

After searching around the internet, I saw people suggest PS3 or Xbox Series X, which can apparently downmix DTS to Dolby Digital 5.1. I don't have an Xbox, but I do have a PS3, so I tried that out and sure enough, after spending like 30 seconds messing with settings, and playing the blu-ray, I'm getting that LPCM 5.1 as the output audio format and it all sounds so much better. There's an actual center channel so I can understand characters, and the surrounds are being used, etc. Apparently if I could find an optical output cable I can probably even get it to Dolby Digital 5.1, too, but not sure if that's worth buying an extra cable for. LPCM 5.1 is a little quiet, but otherwise sounds fine.

So, what's the deal? Is the PS5 a worse blu-ray player than the PS3 or Xbox Series X? That doesn't make any sense. I'd prefer if I could play old BDs through my PS5 to keep 4k capabilities, as it does look a little worse visually on my PS3, but they sound so much better that I'll probably keep using it for now.

Tl;dr: Does anyone know how to get PS5 to output Blu-ray DTS audio as LPCM 5.1 or Dolby Digital 5.1 instead of defaulting to 2.0?

My setup: PS5 hdmi to TV. Soundbar eARC to TV. When I used my PS3, I just switched PS5's hdmi to the PS3.