Decklink Quad 2 Issues

So I recently got a Decklink Quad 2. I have it setup correctly, but for some reason video playback is VERY slow. Like its playing at .3 speed. Is there anything I can do to get the video to playback at normal speed.

how many videos do you play at once? Does it happen also when you only play a single video on a single channel?

Playing one video on one channel. If I setup CasparCG to basically have more than 2 channels the video playback speed is super slow along with the audio. Its not making much sense to me why its behaving this way.

So you say, that you have vonfigured Caspar to have multiple channels, but you see slow play also on one channel. What are the hardware specs? What is shown, when you type Diag into Caspar?

Tried on 4 different machines. Highest end is a Threadripper 2990wx with a RTX 3090 and 128gigs of ram. Down to a Intel NUC Hades Canyon Quad core with 32gigs of ram hooked up to a thunderbolt 3 Sonnet PCIE box. No matter the config it will always play slow if more then one channel is configured. I do not have this issue when using 2 UltraStudio Mini HD’s and a Decklink Duo 2. On any of my rigs.

Tell us what CCG version and post your config file.

2.3.3 LTS server. as for config

  <video-mode>1080p6000</video-mode>
  <channel-layout>stereo</channel-layout>
  <consumers>
    <decklink>
      <device>1</device>
      <embedded-audio>true</embedded-audio>
      <latency>low</latency>
    </decklink>
    <system-audio></system-audio>
  </consumers>
</channel>
<channel>
  <video-mode>1080p6000</video-mode>
  <channel-layout>stereo</channel-layout>
  <consumers>
    <decklink>
      <device>2</device>
      <embedded-audio>true</embedded-audio>
      <latency>low</latency>
    </decklink>
    <system-audio></system-audio>
  </consumers>
</channel>
<channel>
  <video-mode>1080p6000</video-mode>
  <channel-layout>stereo</channel-layout>
  <consumers>
    <decklink>
      <device>3</device>
      <embedded-audio>true</embedded-audio>
      <latency>low</latency>
    </decklink>
    <system-audio></system-audio>
  </consumers>
</channel>
<channel>
  <video-mode>1080p6000</video-mode>
  <channel-layout>stereo</channel-layout>
  <consumers>
    <decklink>
      <device>6</device>
      <embedded-audio>true</embedded-audio>
      <latency>low</latency>
    </decklink>
    <system-audio></system-audio>
  </consumers>
</channel>

Make sure, that the card really get 8 PCIe lanes. And get rid of all these system audio lines in the config.

Will do, its late here. Almost 1AM. Will try and report back tomorrow.

You should try removing system-audio from all the outputs and also try removing latency low. Also what file formats and disks are you using, if you’re files are very large, have you checked that disk I/O isn’t the bottleneck?

From memory thunderbolt 3 is only 4 lanes. I would expect utilising half the card to work fine though.
Are any of the other channels being used in some other software?

That is also my understanding. I think it’s a PCIe issue and not an I/O problem, as he says, that he does not have it with other cards and that he only plays one clip. But we will see.

This is very untrue. I can open up 4 instances of OBS and play out video from all 4 with NO issue. CasparCG has an issue if I setup more then 2 channels

Have you tried playing only in the first channel and routing it to the others?
If playback is OK there, you could try and tweak the FFmpeg threads setting in the config file. What’s the GPU usage when the problem happen?

If you still have problems, you can always use 4 running servers side by side, each one with two outputs.

Also double check the codec. If you use intra-frame compressed codecs, you might find some performance drops. I’ve had much better results using H.264. This issue was addressed partially in this post, and here is an example of that DeckLink working with six outputs from a single server instance (another one was outputting fill+key from the same card)

Thanks for this. I have tried H.264 and ProRes. Both do not work with the Quad 2. I have tried it with a Duo 2 and it works great.

1 Like

Did you reinstall decklink drivers after swapping cards and gone over the settings in Desktop Video (e.g. all set to individual outputs)?

I’ve done 8x 720P with a Quad2 and h264 files before.

Yes I have. This is super weird. I can’t even do 1 720p60 video playback in casparcg. But I can in other programs. This has legit drove me MAD.

So what i am going to do is a clean install of everything and will try to encode videos in h.264.

Ok everything reinstalled and still having the same issue with just the Decklink Quad 2. I have an extra UltraStudio Mini HD laying around, so I tried that and that works perfectly fine.

Hmmm… What about a hardware issue with this card? How long do you have it? Is there still a warranty? I would try with a replacement, sounds too weird.

I had a few of these running without problems, but with Caspar version 2.0.7, probably you can try with that version, just to make sure, that it’s not Caspar (did you mention the version you use? I did not find it now any more).

I have the same problem with Decklink Duo 2. My Caspar Version is 2.1.12 and my config file is pretty basic with only one cosumer. What i found ,if that helps anyway, is that when i set the embedded audio to false everything plays as it should.