Sound f/x Qlab and Focusrite Saffire Pro40

[Herr_Sprecker]

I am experiencing a curious problem with Qlab V2 and a Focusrite Saffire Pro40. This problem did not occur until the middle of this week, possibly coinciding with an update somewhere.

The playback computer is a MacBook Pro running OSX 10.8.5, and Qlab's version is 2.3.9. The Saffire Pro40 has firmware version 1501 and MixControl is 2.4. The Saffire is powered on prior to powering on the MacBook, and demonstrates no issue with connection to the computer. Opening MixControl provides full access to the interface. When we start Qlab, the system still shows the Saffire as an available patch with our show. However, playing any cue results in no audio being sent to the interface. Reboots of all devices and software does not seem to remedy the issue. The only thing thus far that has proven effective is to change the sample rate in MixControl. Once the sample rate is changed, the interface responds properly.

A note on the Figure53 website regarding the Focusrite Saffire 26 noted that closing and opening MixControl would restore functionality. This does not appear to be the case in this issue. Thus far, changing the sample rate around seems to provide the only effective result. We're not using terribly high sample rate files in this show, so we've only been changing between 48k and 44.1k.

This issue began Tuesday (2-4-2014). I could not say for certain if there were any updates to OSX or other aspects of the system on or around that day which might be affecting this.

Has anyone run into anything like this? Or would anyone have any thoughts about what we might be able to do to permanently eliminate this issue? Thanks!

 

[lakota651]

Hi Sprecker,

I am not familiar with the Safire series, but here a few thoughts that might help. In my head I am thinking that the reason you are not getting audio is that there is a mismatch of sample rates between your interface and OSX/Quicktime (from my understanding quicktime cores are used underneath QLab for playback). By changing your interface back down to 44.1 you match the system default and all is right with the world.

First: Have you tried "Repairing Permissions" under the "Disk Utility"? It sometime helps to clear things up when our beloved Macs start behaving unexpectedly. Why this would work in your case is related to my second thought.

Second: Are you familiar with the Audio MIDI Setup utility? If not you can find up by searching Spotlight (the spy glass in the top right corner). Open it up and you should see your Safire listed. Select it, and then look at the sample rate. Then open up MixControl, and see if the sample rate matches. It should, obviously. Next, raise the sample rate in MixControl and see if the change follows in Audio MIDI (a rest of the utility might be needed). If not, then there is a problem with how MixControl or your interface is communicating with the OS (I'm not exactly sure which tells the computer what the interface's settings are). Which might be resolved by repairing permissions. You can also try manually selecting the sample rate yourself, and then see if that works. The value should hold and set to that every time you plug in your interface so you will not have to do this every time.

I hope this helps. Either way, I'm curious to learn what solution/answers you have found.

Cheers!

~ Lakota