MMAL Skipped frame or judder every few seconds

Hi

I’ve just tested with ‘PendelTest.mkv’. I copied it to an SD card and played it back locally using MMAL and Adjust refresh rate on. I see a stutter, and a frame skip when the pendulum flips back.

Does:

touch /var/tmp/.suppress_osmc_update_checks

Improve things for you?

Sam

I would say no. It’s the same as before. Having now rebooted the RPi2 multiple times and playing the same file again and again, I would even say after some reboots there is less noticeable skipping and then I reboot it again and it is more noticeable. I don’t know if this is helping or not or maybe it’s just placebo.

But the skipping is not gone after creating the (.suppress_osmc_update_checks) file in comparison to playing the mkv on OpenELEC. Curious to see what others think.

Edit: I’ve tested running the RPi2 with the Fire TV power supply and the official one (just saying because this will probably be the next question)

Thanks for reporting back.

  • Can you make sure you’re running the Confluence skin?
  • Let’s also try disabling My OSMC:
sudo systemctl stop mediacenter
sudo mv /usr/share/kodi/addons/service.osmc.settings/ /home/osmc/
sudo mv /usr/share/kodi/addons/script.module.osmc* /home/osmc/
sudo systemctl start mediacenter

As a result of disabling My OSMC, some functionality (updating add-ons; profile mode) won’t be functional, but this is just to test.

Thanks,

Sam

Hi

I don’t know if this will help, but I don’t see any stutter using OSMC 2016.02-4 on a RPI 2 with a Digi+, mmal and ‘adjust refresh rate’ on, playing from a NFS share…

Confluence running and disabled My OSMC. Still the same…
It would be a great help if some of the other guys that have the same problems and reported here could test this too. Just to make sure. Sometimes the stutter reminds me of when I bring up the UI mid-film. It’s not always so severe though. Is there nothing in the log I posted?

Did you try the test file or a similar one that makes it easy to spot? Some people are also more susceptible to those kinds of problems. (not saying you are wrong though)

I think I solved it!

It’s the lirc_rpi-module that get’s loaded with OSMC by default. I removed it from the config.txt and no stutter. I loaded the module in OpenELEC and now have the same stutter.

Anyone PLEASE test this out! Remove the dtoverlay line from the config.txt and reboot.

Come to think of it, that line was the first thing I noticed when I switched to OSMC but I totally forgot about it.

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Just to answer your previous post : yes, I tested the same pendeltest.mkv, on 2 RPI2 : one is using omxplayer, the other one (on which a Digi+ is plugged) is using mmal. And no slutter on both :slight_smile:

lirc_rpi_module is not loaded on my devices, maybe because I’m using a cheap IR receiver ?

I think if you set up OSMC new it gets loaded by default. All my fresh installs had the lirc_rpi loaded. I’m not using anything of that sort though. You not having the lirc_rpi module loaded would confirm my results. Lets see if someone else can test this.

It’s set in config.txt by default, but it can be disabled from My OSMC. It’s enable by default to support GPIO remotes out of the box, including the original OSMC remote.

I’m now compiling a new debugging build with Kodi and was talking to @popcornmix this evening. There seems to be a thread which is created and is very short lived during playback. This sometimes correlates to my stutters.

The good thing is that I do see the stutters on PendelTest so can confirm this issue. The bad news is after watching it for 15 minutes today, I do feel slightly hypnotised…

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How is this bad news? Just focus on the sound of my voice… :stuck_out_tongue:

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Having watched a few episodes with OpenELEC and the lirc_rpi module enabled definitely introduced stuttering through the whole episode. Not 100% sure yet if disabling the module in OSMC removes the stutter 100% though. I have to test some more. Lets see what Sam comes up with. Would still be better if a few others could test this out. Where’s @Jdiesel?!

@kartana if you want to wake up people put an @ in front of their name @Jdiesel

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Ah, thanks @fzinken! Wake up @Jdiesel, we miss you! :smile_cat:

I turned off lirc_rpi and watched a 30min clip today and I didn’t notice any stuttering, not 100% sure either but it looks promising.

Sorry I’m away from home and won’t be able to test until later today.

I can confirm that disabling the lirc_rpi module not only significantly improved the studder issue I was having with MMAL playback but also improved remote control responsiveness with my RC6 IR reciever.

this also worked for me!!

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Good find.

cat /proc/interupts doesn’t show me any IRQs when I haven’t got a GPIO receiver attached to the board ,but popcornmix suggests the driver may still be doing something on the transmit side.

I’ll disable this by default in future updates.

Sam

Thanks @kartana

I still notice the odd shudder every so often but rather then every 5 seconds it is now every 5 minutes. I can definitely live with that.

Yeah @Jdiesel there seems to be slight stutter every few minutes for me too. No clue why. Might be the video file but I have no idea how to check the time stamps (that might cause stutter if they aren’t correct). But it seems to happen on most if not all my files so I think that’s not it. Removing the lirc_rpi module did improve things significantly though.