Libreelec 11.0.1 with Raspi 4 4GB Sound Problems

larslunte · April 15, 2023 at 4:49 PM

Hello guys,

I have a sound problem with my Raspberry 4 4GB with Libreelec 11.0.1

Since I bought a new Samsung TV 4k UHD, the automatic detection of my supported sound modes no longer works properly. Various sound modes are missing. Is it possible manually specify the supported sound modes for Libreelec forced?

Between the TV and the Kodi I have an Onkyo Receiver TX-SR875 that supports almost all sound modes in pass-through (DTS-HD, Dolby-TrueHD, Dolby Digital+, Dolby Digital, DTS etc.)

With my old TV all sound modes were detected with Libreelec 9.x without any problems.

Thanx in advance for your help

Lars

**Da Flex** · April 15, 2023 at 5:59 PM

Users often have trouble when switching to 4K due to bad HDMI cables. Make sure to use HDMI 2.0 or 2.1 cables. So data rate will stay high enough to support all audio formats.

larslunte · April 15, 2023 at 7:06 PM

Hello Da Flex,

I use a high end HDMI 2.1 Cable - 4K and UHD are not the problem.

Mostly there are only Dolby Digital or DTS sound available, although better sound e.g. DTS-HD, Dolby-TrueHD are on the source.

Greetings Lars

**Da Flex** · April 15, 2023 at 7:30 PM

The other weak point in the chain might be your AVR. It's possible that the AVR can't handle 4K pass-through without losing audio data.

Can you try RPi HDMI-0 -> TV, RPi HDMI-1 -> AVR?

larslunte · April 23, 2023 at 1:11 PM

Hello Da Flex,

sorry I'm only getting back to you now - I need to get a second HDMI-Mini cable.

With your workaround it works fine, but you have to make many changes to remote control.

So my wife and children have some problems.

Is there a chance to override the supported sound modes for Libreelec forced - this would help ?

Greetings Lars

**Da Flex** · April 23, 2023 at 8:06 PM

Quote from larslunte

sorry I'm only getting back to you now - I need to get a second HDMI-Mini cable.
With your workaround it works fine, but you have to make many changes to remote control.

To my knowledge, CEC signal is only at HDMI-0. So with the workaround CEC should work for the TV, but not for the AVR.

Quote from larslunte

Is there a chance to override the supported sound modes for Libreelec forced - this would help ?

LE gets supported audio modes at boot time. To my knowledge, it's impossible to enforce a specific audio mode.

Another thing you can try with the old RPi -> AVR -> TV setup:

Have a look at LE's audio settings. Maybe you have to switch to a different output device (AVR vs. TV).

Or try this setup: RPi -> TV -> AVR. This is what I'm using.