Blank-screen playback of recorded .ts file with MMAL

I applied the January update to my OSMC Pi last night. This Pi runs with OMX disabled and MMAL enabled, as I find that OMX often gets the deinterlacing wrong with some BBC HD content, sometimes clinging on to film-mode when it should be recognising video content.

Anyway, I noticed that when trying to play back the recording of last night’s Match of the Day, all I had was a blank screen. My Vero’s play the file just fine. On a hunch, I enabled OMX and now the Pi is playing the recording ok. It seems to be specific to this recording, as MMAL was fine with a couple of test BBC HD broadcasts this morning.

This log was captured during the black-screen playback with MMAL, I then enabled OMX.

We haven’t changed anything playback related for Pi in this update - but binary addons, including PVR addons have been updated


I had another BBC HD recording with black screen playback failure on my OSMC Pi via MMAL, so thought I ‘d try my LE Pi and it’s fine. So for now the OSMC Pi is out of service for PVR content as I need MMAL for reliable deinterlacing. Probably a niche problem, but in case anyone encounters the same issue, the update might help.

Are they both running the same version of Kodi?

yes, both running 18.5.

Are kernel and firmware the same?

Can you advise the commands I need to pull that data?

For the kernel
uname -a

For the firmware
/opt/vc/bin/vcgencmd version

Here are the details as requested. I’m going to keep the recording that breaks MMAL playback on the OSMC Pi in case useful for testing an update.

> LibreELEC (official): 9.2.0 (RPi2.arm)
> LibreELEC:~ # uname -a
> Linux LibreELEC 4.19.83 #1 SMP Sat Nov 23 01:55:35 CET 2019 armv7l GNU/Linux
> LibreELEC:~ # /opt/vc/bin/vcgencmd version
> Nov  5 2019 20:41:14
> Copyright (c) 2012 Broadcom
> version b60349918206bf0ce2310de058cf7c5dd0958699 (clean) (release) (start_x)
> osmc@osmcPi:~$ uname -a
> Linux osmcPi 4.19.55-6-osmc #1 SMP PREEMPT Sun Nov 3 22:15:28 UTC 2019 armv7l GNU/Linux
> osmc@osmcPi:~$ /opt/vc/bin/vcgencmd version
> Oct 23 2018 14:41:50
> Copyright (c) 2012 Broadcom
> version 724d81b3f87eb71045e938e572eca140fb8828ab (clean) (release)

I’ve updated the bootloader.
I’ll also give the kernel an update shortly.

Can you give things another go?

To test this update:

  1. Login via the command line
  2. Edit the file /etc/apt/sources.list
  3. Add the following line: deb stretch-devel main
  4. Run the following commands to update: sudo apt-get update && sudo apt-get dist-upgrade && reboot
  5. Your system should have have received the update.

Please see if the issue is resolved.

I also recommend you edit /etc/apt/sources.list again and remove the line that you added after updating. This will return you to the normal update channel.

I ran the update but the problem is not fixed. My Kodi version has changed to 18.6 but the kernel version is the same. The firmware version has changed.

osmc@osmcPi:~$ uname -a
Linux osmcPi 4.19.55-6-osmc #1 SMP PREEMPT Sun Nov 3 22:15:28 UTC 2019 armv7l GNU/Linux
osmc@osmcPi:~$ /opt/vc/bin/vcgencmd version
Mar 10 2020 16:00:17
Copyright (c) 2012 Broadcom
version d5afe412e364adbdafc0394ac65e674091a56473 (clean) (release) (start_x)

It must be kernel related then. We will update that soon.

I stumbled across a fix. I had assumed that I had the Fallback framerate enabled in my PVR playback settings, and it turns out I did not on the OSMC Pi but I did on the LE Pi. Most recordings play fine without it, enabling the Fallback option fixed MMAL playback of the recording. If I disable Fallback on the LE Pi it too gives me black screen playback on this recording.