Sound Cue System unreliability

[Vagabond Players]

Hello Mike,
We have just finished a major competitive theatre festival. We ran our cues three times during the setup of our show without any issues but when the show ran we experienced a loud buzzing on the 3/4 stereo output of our M Audio Fast Track Pro. We have tried four different PC's to run the release SCS 10.4.1. I am advising the four other theatre groups in the area not to upgrade to 10.4.1. Collectively we are experiencing buzzing on our unused outputs of a M-Audio Firewire 410, script errors when running SCS on a PC with anti-virus installed, stuttered playback when media player 11 is installed, and now intermittent buzzing through our USB M Audio Fast Track Pro interface. The mixer board that the M-Audio Fastrack Pro was hooked up to has been tested and verified to be working properly. We ran a show for four weeks, sixteen performances, in January-February without any difficulty. Now we are not able to get reliable playback using the same setup we used before. We have experienced three shows without any difficulty in the last sixteen.
Has anyone else experienced these problems?

Thanks,
Des Renard
Vagabond Players.

[Mike Daniell]

The buzzing through unused outputs of an M-Audio Firewire 410 is an issue that Des reported earlier to me, but so far I've not been able to find a solution to this. I don't have a Firewire 410 and I cannot reproduce the problem with my equipment I do have. I know that several users do have a Firewire 410, so I would like to know from those users if you have had or have not had a similar problem - especially when using 10.4.1.

The stuttering problem is usually caused by buffer underrun, and this can be cured by selecting the Audio Driver option to not use the internal mixer. You mentioned this occurred when media player 11 was installed, so I presume video cues were also included in the production. The processing of the video may possibly have slowed the audio processing logic resulting in the audio buffers running out. So the suggestion to turn off the internal mixer should fix that as the default playback buffer size is increased from 200ms to 5000ms.

What 'script errors' occured with the anti-virus installed? Also, which anti-virus program was installed, and which Windows version?

[Vagabond Players]

Hello Mike,

During the entire show we made the internal mixer adjustment and we are not displaying any video.

We stopped using the M-Audio Firewire 410 after the initial buzzing noise and started to use the M-Audio Fast Track Pro.

The script errors happened when we installed Bit Defender Game Safe 2009 with Windows XP SP3. At this point we switched to a Dell D610 running Windows XP SP2 and Kapersky 2009. Windows automatic Update installed Media Player 11 and we started to experience stuttering during audio playback. We removed Kapersky, audio still stuttered, rolled back to the previous version of Media Player and it stuttered even worse.

We then switched to a MacBook Pro using Boot Camp and XP SP3, with Bit Defender Game Safe 2009, and ran the show without any problems. Last night we setup for our Theatre Festival and ran through show three times without any errors. After the first five minutes of the show we could play out outputs 1/2 of the Fast Track Pro but after experiencing a very loud noise we could only get a loud buzzing out of the 3/4 outputs. When we adjusted the show to only play out of the 1/2 outputs we did not experience any distortion or noise.

After the show we went through the entire mixing console and did not detect any abnormalities or component failures.

Is there a external audio interface you could certify for use with SCS?

Thanks

[Mike Daniell]

I've emailed the developer of the audio library used by SCS and he has advised that "there is a bug in Windows that can cause buzzing when pausing a floating-point channel". He also suggested using software mixing. So could you try setting your SCS Audio Driver options as shown below? Note the settings of the first two checkboxes. (After making and applying a change to the Audio Driver settings, I recommend you close and restart SCS as some of the settings only take effect the next time an audio file is opened, so do not affect audio files open at the time of making the change.)



Regarding the script errors, what do you mean by 'script error'? What error do you get? Is it an error reported by BitDefender Game Safe? A screenshot of the error would be helpful.

With the stuttering, if you are not using the SCS internal mixer and you are using the default buffer sizes (as per the above screenshot) then I can only assume that something else on your machine is thrashing the disk. For example, is there some file indexing program like Microsoft's Find Fast scanning your drive? Task Manager should help identify anything that's making heavy use of the disk, but you may need to select the option to 'show processes from all users'.

I haven't officially certified any particular audio devices for use with SCS, but this is something I should attempt to do. As the number and range of audio devices is huge, I would need assistance from users. I will certainly look into setting this up. Meanwhile, I use an Edirol UA-101 and that has worked extermely well in multi-channel setups.