Pass through not working


I am not able to set an audio pass-through. It used to work fine, but now only stereo PCM is detected by my receiver. When I attempted to switch pass-through ON the video is interrupted. See log.

Can you please advise what would be wrong? My receiver supports the only SPDIF, that is why I use an HDMI audio extractor (KEBIDU 4K x 2K HDMI audio extractor + Optical TOSLINK SPDIF + 3.5mm Stereo Audio Extractor Converter HDMI Audio Splitter|hdmi audio extractor|hdmi audio splitteraudio extractor - AliExpress) because Vevo4k supports 2 ch only via SPDIF.

Thanks for your help.


If you are switching passthrough on while playing a video, try instead to set passthrough on in Settings->System->Audio.


Not to be pedantic but the two PCM channel limit on the tosLink connection is a limit of that standard, not the Vero. It would be just as accurate to say it is because your receiver only supports 2 ch via SPDIF. There is a guide on our wiki you may fine useful…


if the pass-through is set in Settings->System->Audio then the video (with DTS audio) starts, plays for 3 sec without audio and stops without any error message. The DTS is not detected by the receiver within these three seconds (normally there is a DTS logo on). The only format detected (and played) by the receiver is stereo PCM. All this leads me to the conclusion that there must be something wrong with the audio driver. Unfortunately, I do not have enough troubleshooting knowledge.

Why are you using the audio extractor? I don’t see how it can help if your receiver can only handle SPDIF in. Just connect the SPDIF directly to the Vero, set the number of channels to 2.0 and DTS capable receiver to true. You should then get DTS 5.1 on the receiver.

correct me if I am wrong. Agree with you the tosLink limitation is 2ch only when PCM is used. The tosLink build in Vevo 4K supports only PCM therefore 2ch limit. But in case of DTS or Dolby Digital, the tosLink can carry 5.1 channels. My receiver does not have HDMI, it is why I use pass-through to HDMI extractor to extract DTS or Dolby Digital from HDMI to tosLink. Did I miss something?

No, it carries 2.0 LPCM channels, not 5.1 channels.

Re-read the post that @darwindesign linked. Especially the " When using the S/PDIF output of your OSMC device for audio" part.

The Audio hardware and software configuration says:

Which LPCM output formats are supported by OSMC devices via HDMI and S/PDIF?
• Vero 4K/4K +
• HDMI: a samplerate of up to 192 kHz, a bit-depth of up to 24 bit and all channel layouts from 1.0 all the way to 7.1 (the surround center channel of 6.1 is mapped equally to both 7.1 back surround channels)
• S/PDIF (built-in TOSLINK): a samplerate of up to 192 kHz, a bit-depth of up to 24 bit and 2.0 channels

I understand this as build in TOSLINK has a limitation and supports PCM and 2ch only. No way to carry 5.1. Right?

Wrong. TOSLINK can handle 2.0 LPCM. DTS 5.1 can be sent via LPCM 2.0.

Have you actually tried the recommended settings?

DTS and AC3 are transmitted via bitstream. They utilize compression to squeeze six channels into the same bandwidth as the two uncompressed PCM channels.

bhilham, darwindesign,

thanks for the clarification. Let me summarize. My receiver ( definitely supports DTS and Dolby Digital. Therefore direct TOSLINK connection between Vevo 4k and the receiver will do the job - I will hear 5.1 sound and I will see the DTS logo on receiver’s display :slight_smile: when pass-through is selected. No need to involve HDMI extractor. :frowning:


I will follow the guide step by step tomorrow. it is too late today. :slight_smile:

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