[RPi4] Sound stops when overlays are drawn for h265 files using both HDMI ports

IRDC · May 2, 2025 at 6:13 AM

Hi,
up until now I had my RP4 with LibreELEC 12.0.2/KODI 21.2.0 connected via HDMI0 to my AVR and everything was working fine (everything being MKVs from my DVDs and Blu-rays; mpeg-2, vc-1 and h264).
A few days ago I added my first video files with HDR (MKVs from my UHDs; h265) and noticed that my AVR (Onkyo TX-SR444) was not able to passthrough HDR material to my TV. I tried connecting my RP4 directly to the TV which gave me HDR but the ARC from the TV to the AVR wasn't able to passthrough Dolby-HD/Dolby Atmos etc. That's when I decided to buy another HDMI cable (cheaper than buying a new AVR) and connect my RP4 to my TV on HDMI0 and to my AVR on HDMI1.

I changed the settings to output decoded audio to the TV (mainly KODI's menu sounds) and passthrough PCM to the AVR.

When I watch "non-HDR/not UHD-based/mpeg-2, vc-1 and h264 movies" I have no problems. (I had some problems with a Blu-ray-based movie with Atmos sound but that went away after some restarts...)
When I start playing a HDR/UHD-based/h265 movie the sound will start playing back via the AVR (Atmos indicator lighting up correctly) until a change to the picture happens (e.g. I use the remote to open a menu or the first subtitle gets displayed). That's when the audio stops and won't come back (for any movie) until I restart the RP4.

Has anyone encountered similar problems?

**chewitt** · May 4, 2025 at 4:48 PM

popcornmix any ideas?

IRDC · May 15, 2025 at 7:36 AM

Is there anything I could test or log to help find the cause of the problem?

**popcornmix** · May 15, 2025 at 5:06 PM

No real ideas. After a failure run "dmesg | pastebinit" and post the url just to see if anything complained in the kernel.

If it were me, I might try adding "force_turbo=1" to /flash/config.txt.

If that didn't work, I might try a core_freq overclock (note: too high and this could crash - backup before experimenting).

Start with core_freq=600 (but you could try 700 or 800).

IRDC · May 17, 2025 at 11:37 AM

I started 3 movies. The first 2 were mpeg-2 and h264 had no problems, the third was h265 and worked until the moment I opened the menu. The picture wasn't affected in any way but the sound suddenly stopped (the AVR's indicators for Dolby-HD/Dolby Atmos went out), that's when I ran "dmesg | pastebinit":

https://paste.libreelec.tv/eternal-meerkat.log

**popcornmix** · May 17, 2025 at 12:58 PM

Quote from IRDC

I started 3 movies. The first 2 were mpeg-2 and h264 had no problems, the third was h265 and worked until the moment I opened the menu. The picture wasn't affected in any way but the sound suddenly stopped (the AVR's indicators for Dolby-HD/Dolby Atmos went out), that's when I ran "dmesg | pastebinit":
https://paste.libreelec.tv/eternal-meerkat.log

Nothing unusual in there.