It's such a random and unpredictable and unrepeatable problem that I think only time will tell if it's fixed.

Yes its a nasty one for sure.

Just reading over the posts from the begining and thinking what it could be (or hopfully .. was) going on here.. So heres my 10ps worth.
Some posters have said that once a media file was 'replaced' on the time line, its properties within vegas showed the correct file references. And this was stated by more than one person when they checked it. So, lets say, if on exiting the program the project file gets screwed (its media reference locations) then when the project file is later re-opened, we would see the 'media references' as incorrect. The damage already being done from the previous save. Well, we dont see that. So i suggest the references are being damaged upon loading in the project file.[or during an edit session].
Not sure what happens to the media references in the project file after damage occurs, are they then saved back to the project file? If there no damage to the project file at all, in other words, after a corruption, does a simple re-load of the project file correct the error? If so, then its internal to Vegas only and its not reading the project file correctly as it comes in.
I wonder if exporting an EDL list after the replaced media occurs would help, would the references show as correct. And if re-loading the project file does not clear the error, then something else is at play. Does Vegas use SQL at all (like SQL lite) for its media cross referencing?

Does that make any sense?

Paul.

in other words, after a corruption, does a simple re-load of the project file correct the error?

Not in my case unfortunately...I say that because one time I had many clips replaced but didn't fix all of them (because I was working with hundreds of clips and I couldn't determine what clip was supposed to be in that position) and noticed when opening again later the same clips were still wrong...not sure if they were still replaced with the same wrong clips but I know they were wrong.

I just got bitten by this bug for the first time. I was using Sony Vegas 10.0e 32-bit in Windows XP x64 (unsupported, I know), with "Close media files when not the active application" checked.

I was working in a big, complex project with about 800 video events in it. Over the past few days I have been opening a second copy of Vegas to do some complex corrections on 7 of these files, so I've been copying and pasting events between the 2 projects. This is not something I've done much of in 10.0 until now, so that might be why I haven't seen it until now. Today, when I opened the big project, the media of 5 video events on the timeline had been replaced (but the filename in the active take information had not been replaced). 4 of the 5 had been replaced by media that I was working on in the small project (of which there are only 7).

So in my case this bug seems to be related to copying events between 2 instances of Vegas, or at least having the same events open at the same time in 2 instances. From now on I'm going to do as atom12: "Now anytime I need to open multiple instances to move footage I first "save as" to a new name, delete all the footage that I'm not copying, save again, then do the copy/paste."

I managed to repair my project like this:

1. With the media generator, create a temporary "dummy" event for each of the messed up events and bring them into the project.
2. Copy and paste event attributes from the messed up events to the new dummy events (to retain FX and panning/cropping).
3. Note down the "Take Start" time of the messed up events from the "Event Details" window.
3. Delete the messed up events.
4. Project Media window > "Remove All Unused Media From Project" (the lightning bolt).
5. Save, exit, re-open Vegas.
6. Project Media window > Right click on each dummy file > Replace with the correct files.
7. Adjust the "Take Start" in the "Event Details" window.
8. Save, exit, re-open Vegas and check.

I've also unchecked "Close media files when not the active application" (but I have a nagging feeling that is required to fix some other Vegas issue???).

Please please please SCS, do the right thing and give us a 10.0f with this killer bug fixed, if you know how. You should encourage us to purchase major new releases for the features, not for bugfixes.

Thanks Nick for the steps in how you resolved your problem. The dummy event with attributes pasted is an idea I hadn't thought of before. Nice.

I also want to add to this thread my name as one of the first (and encourage others too) to officially ask Sony for a 10f release with the bug fix for this nasty problem. Let other customers add their names to this thread who also want to officially ask Sony for a 10f release.

Erik Davis
Sony Vegas user since 2007 Owner 2 Seats V8, V9; 1 Seat V10, V11

Just happened to me again but FWIW, I just thought I should mention here; for the first time ever when I selected "show in media pool" it pointed to the corresponding file....not the one that was supposed to be on the timeline but the one it was actually playing.