Solving playback issues

[Joeboo]

I have a Roku ultra 2020 as well as a Vizio 5.1 sound system. The roku audio settings allow me to have different choices: PCM, pass through, DD Plus, etc. For some reason only passthrough allows my side speakers to work. Anyone know why that is or if I should be doing something different? Thanks.  

[StreamerUser · Accepted solution]

---

@Joeboo wrote:

I have a Roku ultra 2020 as well as a Vizio 5.1 sound system. The roku audio settings allow me to have different choices: PCM, pass through, DD Plus, etc. For some reason only passthrough allows my side speakers to work. Anyone know why that is or if I should be doing something different? Thanks.  

---

You want "Auto passthrough" - "Auto detect" transcodes/converts all non-DTS output to the highest detected Dolby level (E.g PCM MAT 2.x/Atmos, or DD+/Atmos, etc etc) of the connected device (regardless of # of channels etc - you dont want that).

Just leave it at auto-passthrough unless your audio drops, then you should toggle it to auto-detect, then back to auto-passthrough.

[Sawtaytoes]

From what I understand, passthrough sends the audio bitstream directly to your receiver or TV rather than having the Roku process it.

My Roku Ultra 4800R has these settings:
- Auto
- Passthrough
- Stereo
- Custom

The "Auto" setting does some funk things and converts all audio sources to Dolby Atmos over Dolby Digital Plus.

"Stereo" is obvious converting all audio to 2-channel.

"Passthrough" is what allows my receiver handle any audio from the source (Roku app) rather than from the player (Roku Ultra) allowing it to support more kinds of audio streams. But I might be wrong here. It may be that the Roku, or its apps, need to support those formats for passthrough to work.

It's hard to test since most online media is Dolby Atmos over E-AC-3 (Dolby Digital Plus) with no DTS to test even though the Roku specifically supports DTS and outputting over DTS through Plex.