Ultrastudio 4k + ProTools 12..problems galore

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Ultrastudio 4k + ProTools 12..problems galore

PostThu May 05, 2016 10:14 am

I have been having some crazy problems when using the US4K with Avid Pro Tools, and have spent ages trying to resolve them. I have found an unsatisfactory workaround and am hoping you can suggest a different solution.

I have two edit suites, both running Mac OS10.11.4 on Mac Pro's. Each has its own Ultrastudio 4k & Smartscope Duo.

The main problem is that a while ago (when it was a single edit suite) I was advised that if i wanted to record audio in ProTools, with a feed going into the US4k, i needed to provide the device with a video signal as well. At the time the only source i had was a Sony digibeta video deck with unbelievably loud cooling fans, making it impractical as the long term source.
The US4K was fed with a tri-sync ref signal from a BM mini converter sync generator.

It worked, but also involved rebooting the US4k and resetting its inputs whenever i wanted to record anything. Then resetting and rebooting once the Sony was switched off.

Now i have just finished installing the second suite and have tried to make a more usable setup but there is something going wrong and its causing ProTools to refuse to respond whenever the video track is switched on.

What i have done is to feed a Colour Bars test pattern from an Atomos Connect-AC device (i have tried a few different frame rates (pal, 1080 26p, etc) into one of the SDI inputs, at the same time as sending a sync signal to the ref input.
In this setup, the Protools log shows an error message saying "it cant play the video as the network clock is not locked."

I tried various combinations of syncing the US4k and Atomos by connecting
a: atomos output into USk4 SDI IN + BM Sync to Ref In
b: atomos into BM Updowncross + BM Sync into Updowncross and US4k Ref In

The only way i have found to cure this is to remove the video input from the US4K. This stops the clock problem and allows ProTools to playback audio and video correctly. However, I cannot record audio from an external source such as a Mic preamp.

Also - I have noticed that when i feed the test signal into the US4k's, i cannot see the signal on my monitor or the front panel monitor. The DesktopVideo Utility shows that the signal is being seen, but i cannot find a way to display the result on a screen.

If i feed the test signal directly into a monitor, then it shows a Colour Bars pattern, and the onscreen info shows the correct frame rates.

I am now wondering if there is a problem with how the US4k actually sees and processes the incoming video signals. As all my material is brought in as files rather than video inputs, its only now i am finding this discrepancy.

The exact same problem is occuring on two different systems - one has been installed over a year, the other is brand new.

Any advice or suggestions how to cure this problem would be really appreciated.


I have also sent this to BMs tech support so if i get a solution i will add it here also.


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Re: Ultrastudio 4k + ProTools 12..problems galore

PostThu Oct 19, 2017 2:34 am

Were you able to find a solution. Sync for me is a constant question and I have no idea how to actually test it other than playing a known synced video and then listening and watching the video....
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Re: Ultrastudio 4k + ProTools 12..problems galore

PostThu Oct 19, 2017 7:29 am

I had to stick with changing the settings on the desktop video driver if i ever needed to record audio via the US4k. However, since switching my video editing to Flame, i have been totally screwed when it comes to audio! Basically, Autodesk say i must use v10.6 desktp video, but Blackmagic say NO - that driver has loads of known problems with audio conflicts.

I cannot even start ProTools with that driver in the system...so i have to do my audio edits on the laptop now.
I'm just waiting for the day all the manufacturers get their software working together with each other before releasing it into the world. So probably never!

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