Blackmagic Forum

Hello everyone,

My first post here, although I've been using Resolve for some time now and Fusion since v3. Usually I edit personal stuff and some screencast videos under Windows but a couple of months ago I decided to switch to Linux (Fedora 25). Both Resolve and Fusion (free editions) work great except for the audio issues with Resolve (no audio unless a BM card is installed). So, after the price drops in both apps I decided to buy a DeckLink Mini Monitor (as well as studio versions for both apps, which I'm still waiting for hehe).

Today I received my card and installed it. Installed the drivers, as well as the Desktop and Media Express apps. Launched Resolve (12.5.6.017), opened the preferences window and under "Video I/O and GPU" now there's DeckLink Mini Monitor... cool, so far so good. So I selected that as my playback device and checked the "Use system Audio Output" checkbox. Saved the preferences and before restarting Resolve, I opened the project settings to make sure "Enable Audio Output" was also checked under the "Capture and Playback" section.

Closed and relaunched Resolve, opened this same project and found out that no matter what, I still have no audio output. I refuse to think that the only way to get it working is by spending some more bucks to get a HDMI audio splitter, and then having to connect those outputs to my sound card (external USB soundcard btw). I think I'm missing something here but I have no clue on what can it be.

Does anyone know how to passthrough the audio from the DeckLink card to the system audio device under linux?

Just to let you know, I can hear audio from any other app (vlc, chrome, audacity, etc)

Thanks in advance for any help, I really appreciate it,
Orlando.

...And here's the log

There is currently no system audio on Linux. You will need to use the Decklink audio.

Orlando Esponda wrote:I refuse to think that the only way to get it working is by spending some more bucks to get a HDMI audio splitter, and then having to connect those outputs to my sound card (external USB soundcard btw).

maybe you could use the audio output of your monitor for this purpose?
but i also don't like this solution. it's very unsatisfying to change the preferred audio routing just for one application.

in studio setups, where resolve is used as the only application at one seat, this may not be seen as an importand issue and you may even gain some benefits concerning synchronicity using this kind of audio transport, but on a general purpose workstation it's indeed a very annoying hindrance.

But if there is any latency in the system or the Decklink, you'll work out of sync.

Peter Chamberlain wrote:There is currently no system audio on Linux. You will need to use the Decklink audio.

Thanks for your answer Peter,

To be honest this is disappointing. I'm glad there's a linux version of Resolve, and I understand that some features are not available in the free version. I'm not talking about main features, but h264 support for instance. It's kinda contradictory having a free app and not being able to use the most common formats. But up to certain point I do understand and that's why I ordered my license for the studio version. I would also understand that a requirement for the audio support on linux was tied to a piece of hardware... after all we are getting lots of things for free and it's a way to contribute to the development. What I don't get is this... how many people use a computer monitor (or a hdmi cable for that matter) as monitoring system? It feels incomplete. I have audio monitors and a pair of good headphones for anything audio related, and seems like I won't be able to use them (at least not in the short term, until I get a good audio converter and a patch bay).

Don't get me wrong, I think you guys are doing a great job with your free versions, but it will be useless for most of the guys out there using linux (unless they decide to buy the DeckLink card and use their monitor speakers). Linux laptop? big no because I guess they won't want to carry some converter, cables and speakers with them. The funny thing here is many people move to linux from windows, but audio works just fine there.

Last but not least, please let people know this. If I knew it probably I would just keep booting in windows for Resolve (which actually I will need to do even with the DeckLink card, until I find the right equipment to make it work). Before I ordered the card, I spent hours trying to find out how to have audio under linux. I (mis)understood that with the card I would be able to use the system audio as all the related posts say.

Martin Schitter wrote:maybe you could use the audio output of your monitor for this purpose?
but i also don't like this solution. it's very unsatisfying to change the preferred audio routing just for one application.

Thanks for the suggestion Martin, I will look into it. I use Display Port but I think there's no difference these days and perhaps I can use my monitor's headphone output while actually looking at the DP signal (don't want to lose 1 of my 2 screens). No audio monitors but at least headphones


Just my 2 cents,
Orlando

Uli Plank wrote:But if there is any latency in the system or the Decklink, you'll work out of sync.

let's think positive and assume, that decklink hardware always behaves nice and doesn't entail nasty latencies, in this case everything will work fine, because linux system audio also works very well, reliable and predictable.

Uli Plank wrote:But if there is any latency in the system or the Decklink, you'll work out of sync.

There's an "Offset audio by x frames" preference. I'm guessing here because I haven't been able to try it, but for what I read in the forums and what I read in the manual, it can be used to compensate any latency:

Manual p. 954:

Offset audio by x frames: Lets you specify an offset between the audio track and video
to achieve proper A/V sync in cases where the video is being delayed by outboard
processing hardware.

Yep, that should help.