BMD Output not working

Hi all,

This is a strange one… I can’t seem to get any video to output via BMD Decklink on one of our Linux boxes. This machine is running Rocky Linux 8.7/ Flame 2025.2.2 / DKU 19.2.0

In the ‘setup app’ I can choose BMD for both video/audio and when I go in to Flame I can select BMD under ‘broadcast monitor’ and I select my format of 23.976 or 59.94i (both at HD)… but then nothing comes out. It’s just black. I’ve manually re-installed the Blackmagic Decklink driver v14.2
In the ‘hardware validation’ app, Flame appears to be able to detect the card and identify its slot position.

In the shell I can see:

Bad Audio: ERROR applying the interface: Bad error for Cannot get audio input value.: (

BMD: Failed to set SDI output

BMD: Failed to readback SDI input configuration

I’m scratching my head… anyone have any ideas?

Update the firmware of the BMD card

I did this in /usr/bin: ./BlackmagicFirmwareUpdater status
and it returned the following:
0: /dev/blackmagic/io0 [DeckLink Mini Monitor 4K] 0x11a OK
Does that mean it’s up to date?

Maybe the card is bad? Did it used to work?

I’m running 2025.2.2 / 19.2 / RH 8.7 with a 4K Extreme in 23.976HD and have no problems.

My firmware utility says 0x127 OK, but it may different since you’re on a 4K Monitor card.

If you have another system with similar hardware, try swapping the card and see if it follows system or card.

Swapping the card into a different system is a good idea. I’m hoping I don’t need to do that, but that definitely makes sense.

Another thing I just tried… I just installed BMD’s MediaExpress rpm
I opened a ProRes .mov in it and the card DID in fact output video/audio.
So… I think the hardware works. For some reason Flame isn’t able to use it though.

Good data point.

Two additional thoughts:

  • These cards can only be used by one app at a time. On Mac, if I have Switch (QC player) open with the card, and then run Resolve, it has a heart attack every 45s. Any chance there is another software other than Flame running that may have the card open? For example Nuke?

  • And how are you determining if there’s video or not? Just via the attached monitor? There are a few video modes you can select in Flame that don’t work with my FSI monitor. In particular the psf vs p variations of the 23.976 frame rates. So I wonder if you have a false negative.

Although you are getting error message that seem to think Flame is unhappy. Though they could be the standard sync not detected problem. Did you change the config to freesync in the setup utility?

All good thoughts (and greatly appreciated by the way)

This machine is a Linux Flame that does not have Nuke or any other video apps installed (other than the freshly installed BMD Media Express I mentioned) . So I don’t think it’s that… but I love the logic.

As far as determining if there’s video or not… I’ve tried a monitor as well as our BMD Video Hub. I’m only really trying 1920x1080 23.976psf (freesync) and 1920x1080 59.94i (freesync)

I would also try 1920x1080 23.976p (not psf)

And right on cue, my system acted up :slight_smile: Flame crashed for unrelated reasons and left the BMD card stuck in state. Upon app restart of Flame it can’t talk to the card.

It tends to timeout after a while. But I was also just googling it, you can have it re-numerate the hardware with this command:

sudo modprobe blackmagic_io

not guaranteed to clear it. In my case the driver finally timeout and reset just was I was Googling the details.

I wish there was reliable command line to reset the BMD driver/card without having to reboot.

-u -a

i’m not sure I understand… is that like “update all”?
Where do you use it?

yeah… i did run “update” as well. I think you do it with ./BlackmagicFirmwareUpdater -update 0x11a (in my case).

Is there something else to try there?

Make sure you have BMD set for all the necessary resolutions in the flame set application, Preview tab.

for sure. In fact I cross referenced those settings against the values found in /opt/Autodesk/FLAMEVERSION/cfg/init.cfg

All looks normal. It just doesn’t work.

Which version of Desktop Video do you use on the Linux workstation?

What do you see when you start Blackmagic Desktop Video Setup application?

Hi @Slabrie It’s versions 14.2. As far as what I see in the BMD Video Setup app goes… On the main screen I just see “Video Output 1080i/59.94” over SDI + HDMI. Is there something within this application that I should look for specifically? In BMD’s “Media Express” app, I’m able to import a .mov and play it out over SDI.

Thanks in advance for any thoughts/advice you might have!

Could you screenshot the Preferences / Project / Broadcast Monitoring window and the Preview tab in Setup application?

What do you get after a reboot?

Apologies for the iphone pics instead of screenshots… my setup is atypical today. After a reboot the issue persists.