Audio bug in Vegas, bit like the flash frame problem.

farss wrote on 9/12/2004, 5:58 AM
1st clip, intro with music. 2nd clip nice long sports event. Trim some black from front of second clip, butt up to end of 1st and add around 2sec fade up on audio. Didn't realise I'd overlapped the two clips a few frames and I had Auto xfades off but the T/L shows a cross fade and about 2 seconds into the second clip I get a few notes of the intro music. Remove the overlap and the problem goes away. Yipes.
Thanfully I noticed and it's only kiddies football, hate to have that go unnoticed in the midst of something important. Seems very easy to repro. Oh and yes V5 latest build.
And one other really odd thing, increase the length of the overlap and the problem goes away. And no ripple edit being used either.


Bob.

Comments

SonyEPM wrote on 9/12/2004, 7:18 AM
Is one of the events looping?
farss wrote on 9/12/2004, 7:34 AM
No, unless you mean in media properties, haven't checked that. If you want me to sorry, I have a 6 projects batch encoding now so will be tomorrow before I can check that.

Bob.
farss wrote on 9/14/2004, 8:07 PM
This problem is still there and I've turned off 'Loop' in media properties and I'm now getting it even without overlapping the events.

Anyone have any thoughts, I now cannot find anyway to stop it happening!

Bob.
Spot|DSE wrote on 9/14/2004, 9:50 PM
Bob,
Are these MP3 files by chance? Or any other encoded file format that might contain metadata?
farss wrote on 9/15/2004, 12:28 AM
SPOT,
good to see someones listening.
No mate, just plain vanilla .avi files. First one is a clip from a DV tape client gave me, cut it up in Vegas and rendered out this bit to go at the front of the main event.
Second clip is from DVCAM tape of main event. Adding a fade up on the audio at the start of the second event brings on the problem.
About 15 seconds into the second clip I get a few notes of the into music playing in the soundtrack.
Putting a 1 second empty event between them seems to cure the problem, very strange stuff. Couldn't be a simpler project, one video and one audio track, not like I'm taxing things! The really odd thing is I've done 100s of Vegas projects and it's just coming up on this clients stuff. For what it's worth he shoots on high end Sony DVCAM kit and I'm capturing off my DSR-11. Doesn't get much more straightforward than that. The ONLY odd thing is on the original tape the first clip came from had 32K audio (he blames it on his FCP system!) but I've rendered it out as 48K in Vegas just to be certain I would get any funny business and now this!

Bob
farss wrote on 9/15/2004, 6:02 AM
Some more detailed details:
To repro this problem, auto xfades off, put fade up at start of second clip and then slide say 1 frame over top of first clip. You'll see that the first clip shows a fade down for the duration of the overlap.
Play out and you'll get a few beats from the first clip mixed into the second clip a few seconds into the second clip.
Slide the second clip so there's no overlap and the problem disappears.

Hope this helps someone to repro the problem, if it makes any difference, stock standard PAL DV project.

Bob.
Spot|DSE wrote on 9/15/2004, 6:36 AM
Bob, I can't repro here....Tried with both Acid loops and with straight avi. Neither is giving me the issue you apply.
I know that sometimes Vegas seems to hang on to information in RAM, and it will randomly pop up if the combination of things just happens. I saw that occasionally on the VASST tours when doing lots of little things and not refreshing at all...I wonder if your RAM is just hanging on to stuff.
Try re-creating the problem, then right click the Windows Task bar, select Properties>Start Menu>Customize>Advanced, and Clear List. See if that fixes it.
farss wrote on 9/15/2004, 2:08 PM
SPOT, thanks for taking the time to try to repo, I'll try what you've suggested once I finish the current round of captures. I'd have imagined what you're saying would be more likely to happen with video than audio though.
It does seem related to the cross fade that's been applied to the audio. What I see happening on the TL is a asymetric cross fade. Having already applied say a two second fade up on the second clip but only overlapping by one frame the cross fade is forced to being only one frame long. However Vegas is perhaps trying to match the two halves of the crossfade and effectively repeats the first clip to fill in the non existant gap. This may go back to what SonyEPM was asking about. Following on from his question I tried disabling the 'Loop' flag on both clips but that doesn't seem to have made a differrence.

Will play with it some more and report back. Like I say not really a problem for me but it'd be good to know why it happens.

Bob.