Audio Problems when Rendering Regions

Wayne wrote on 12/5/2003, 4:16 PM
I am having audio problems when rendering regions with muted audio and video tracks.

What I am doing when this happens is:

1. I am rendering regions.
2. I have 2 or 3 video tracks with all but one muted.
3. I have 3 or 4 audion tracks with all but one muted.

What I am doing is syncronizing 2 or 3 camcorder video/audio tracks and one DAT audio track. I then add markers for seperate takes and render the take region for each of the video tracks with the DAT track. One I was doing recently had about 10 takes using 3 cameras.

I mute all the audio tracks except the DAT track. Then for each take, I render as a region each camera to a seperate AVI file.

I never have any problems with the video. I render each camera for the first take, open a second session of Vegas 4 and preview the files be verify they are rendering correctly. These first three had a few seconds of garbled audio and then no audio. I then deleted these renders, went back to my main session and cycled the mute switch in the DAT track a few times and re-rendered the three cameras. This time I got good audio. I always seem to have muting problems with only the first rendered set.

On to the other takes, some rendered fine, some garbled. I experimented with cycling the muting of both video and audio tracks. Saving the session, closing V4 and then reopening. Randomly I was able to get good audio, but I could not see anything whch I did that would correct things consistantly.
As I am going through the session, I am marking the ends of a take, then rendering each of the three cameras and then marking the next take and renderng it and so on.

When I do get a good or bad render, it is for all three camers.

I have had the problem on several projects now with the same type symptoms.

If I render the entire session, I don't have the problem, only when rendering regions, with tracks muted.

The garbled audio sounds like the track is being played backwards, but I have played the garbled AVI files backward and it doesn't make it correct.

Comments

TheHappyFriar wrote on 12/5/2003, 9:25 PM
What version of Vegas are you using?

This sounds strange.. Have you tried playing your media files in media player to confirm they aren't messed up? Also, what are the audio settings of the project compared to the settings of the audio itself (bit's, khz, etc). Another thing to look at is the sound driver vegas is using. Options-Preferences-Audio Device. I've had problems with using the DirectX driver (Direct Sound).

Do you have any software installed on your system running in the background (norton, mcafee, etc)? And do you have any software that could possibly mess with the sound settings (like winamp playing)?

It's a wierd error. I've never heard of it, so all the system info you culd give would help.
Spot|DSE wrote on 12/6/2003, 7:46 AM
What audio card are you using? How are you importing the DAT audio? SPDIF? Does it by chance have SCMS on it? Any busses set up, with FX running to the busses? I've never heard of this either, this is a strange thing.
Since muting isn't automatable, it seems there is perhaps a sample rate issue happening. Garbled/backwards would be indicative of that.
Can you post a stream somewhere?
Tried reinstalling Vegas as the last installed software, or doing a repair install?
Wayne wrote on 12/7/2003, 7:43 PM
I was running 4.0 c and d when I had the problem. I downloaded and installed 4.0e Friday night, rendered two more takes (X 3 cameras) and re-rendered an existing take with no problems.

It looks like either the 4.0 e release had a fix to my problem or else the reload cleared a dll file or similar problem. I am believe my problem was a bad load since no one else has report a similar problem.

I am sure it was a render problem and not the original wave file or sound board problem because I could play good renders repeatedly with no problems and the original wave file played with no problems on the time line.

I also got where when I got a garbled render, I could look at the waveform on the timeline, delete the avi file and waveform file, re-rendered it, bring it on the timeline and by looking at the waveform tell of this render was garbled or not.

Thank you both for your responses.

Spot, I assume that when to talk about a repair install, this is simply reloaded the application and allowing it to overwrite the exe and dll files.

If the problem occurs again, I will repost.

Thanks,
Wayne