No 5.1 audio on V31

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jfabernathy
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Posts: 175
Joined: Wed Feb 18, 2015 2:37 pm
United States of America

No 5.1 audio on V31

Post by jfabernathy » Sun Mar 22, 2020 5:44 pm

I now have v31 running okay on my RPi4 4GB with the exception of 5.1 surround pass-thru.
aplay -L shows these sound devices.

Code: Select all

i@raspberrypi:~ $ aplay -L
null
    Discard all samples (playback) or generate zero samples (capture)
default:CARD=ALSA
    bcm2835 ALSA, bcm2835 ALSA
    Default Audio Device
sysdefault:CARD=ALSA
    bcm2835 ALSA, bcm2835 ALSA
    Default Audio Device
dmix:CARD=ALSA,DEV=0
    bcm2835 ALSA, bcm2835 ALSA
    Direct sample mixing device
dmix:CARD=ALSA,DEV=1
    bcm2835 ALSA, bcm2835 IEC958/HDMI
    Direct sample mixing device
dmix:CARD=ALSA,DEV=2
    bcm2835 ALSA, bcm2835 IEC958/HDMI1
    Direct sample mixing device
dsnoop:CARD=ALSA,DEV=0
    bcm2835 ALSA, bcm2835 ALSA
    Direct sample snooping device
dsnoop:CARD=ALSA,DEV=1
    bcm2835 ALSA, bcm2835 IEC958/HDMI
    Direct sample snooping device
dsnoop:CARD=ALSA,DEV=2
    bcm2835 ALSA, bcm2835 IEC958/HDMI1
    Direct sample snooping device
hw:CARD=ALSA,DEV=0
    bcm2835 ALSA, bcm2835 ALSA
    Direct hardware device without any conversions
hw:CARD=ALSA,DEV=1
    bcm2835 ALSA, bcm2835 IEC958/HDMI
    Direct hardware device without any conversions
hw:CARD=ALSA,DEV=2
    bcm2835 ALSA, bcm2835 IEC958/HDMI1
    Direct hardware device without any conversions
plughw:CARD=ALSA,DEV=0
    bcm2835 ALSA, bcm2835 ALSA
    Hardware device with all software conversions
plughw:CARD=ALSA,DEV=1
    bcm2835 ALSA, bcm2835 IEC958/HDMI
    Hardware device with all software conversions
plughw:CARD=ALSA,DEV=2
    bcm2835 ALSA, bcm2835 IEC958/HDMI1
    Hardware device with all software conversions
pi@raspberrypi:~ $ 
I'm use the default:CARD=ALSA and I have stereo sound coming from my system but if I switch it to 5.1 and select Dolby and DTS it's has only a buzzing sound

(BTW my HDMI from the RPi4 goes to an AV receiver which drives the TV via HDMI out and the speakers via direct connectors)

jfabernathy
Senior
Posts: 175
Joined: Wed Feb 18, 2015 2:37 pm
United States of America

Re: No 5.1 audio on V31

Post by jfabernathy » Mon Mar 23, 2020 3:20 pm

here's some additional data.

My HDMI connection is to the MicroHDMI connector nearest to the Power USB-C connector.
In the default: CARD=ALSA I only have Stereo and if I check any of the digital audio capabilities and turn on 5.1, I get the buzz.

However, if I select device:hw:CARD=ALSA,DEV=2 I can check only E-AC3 and then I have 5.1. I have no idea why, but the System information screen showed my conection was HDMI1 so I saw in aplay -L that that corresponded to DEV=2 on mythtv.

Now when I turn on 5.1 I have Surround sound. I'm guessing that DTS and Dolby Digital in Mythtv audio setup must mean Optical or Coaxial Digital audio connections??

I figured this out while trying to get Android mythfrontend v31 working on a Shield TV with 5.1 E-AC3 is the only option there that works. The comment on that options show HDMI connection only and Dobly and DTS show digital audio connection.

BTW, my RP4 hdmi is connected to an AV receiver. The receiver drives the speakers and passes the video to the TV via HDMI.

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