In Sony Vegas Movie Studio 4.0, everything works ok but the playback preview's audio is choppy. Any ideas?

Question

I could probably do a much better job of explaining this, but you know the little box in the corner that you can preview your video so far in? Well, whenever i play that the audio is always choppy but still pretty well synced with the video. There's probably some quality setting im overlooking, but im just not sure why it does that. If anyone can help me I'd really appreciate it!

Answer 1

What kind of computer? CPU speed? If it is a laptop or older tower with a slower CPU, this could be a contributor to what you are experiencing. Resolution: faster CPU.

RAM? If you don't have a lot of RAM - um... less than a gig... two things happen, first, the application does not have enough room to do work, so it is relying on virtual memory (on the hard drive) which is slower than regular electronic memory. Resolution: More RAM. 2 gig minimum.

Available hard drive space? Disk fragmentation? If you don't have a lot of RAM and you don't have a lot of available hard drive space, the editing application does not have any RAM to work with. If you have not defragged the drive  in a while, the virtual memory is not in contiguous space so the hard drive heads have to go all over the place because the virtual memory is all over the place... Resolution: Defrag the hard drive (Tip: never run a disk with less than 10% free space).

And last... if you also include that the computer editing is being done on a laptop, most laptop hard drives spin at 5400 RPM. They were not really designed for video - or video editing. Most external or tower 3.5 inch drives spin at 7600rpm... that helps a lot. The really good drives spin at 10,000rpm... this all has to do with the speed that data can be retrieved (or written to) the hard drive... Resolution: Use an external firewire connected drive if you are on a laptop or tower - if on a tower, install a second drive (if there is space available that does ONLY video project data file storage.

All of these factors can impact video playback. So if one or more apply to your situation, I would not be at all surprised at the symptom you are reporting. Remember, you're in an editor - not a regular "player" application. When you export the project to a file or DVD, if the video and audio is OK, then you should be fine... If this is a problem, then there is something else going on.

Answer 2

There are quality options, but I can't remember how to change them in VMS 4 - it's now a button above the preview window.  That said, if the preview's choppy it's probably not a quality setting.  Vegas generates the preview in realtime, including any effects and transitions you've added, so processing power may be an issue - do you have the same problem if you play an unmodified clip?  What video format are the clips in - if you're using MPEG that slows things down a lot!  Do you have a lot of other apps running while you're editing?  Try killing off as many as possible - some people isolate their PCs and then switch off anti-virus and firewall apps when they're editing.

Disk speed could be an issue - defragging the disk might help (some people swear by it, I'm more inclined to swear at it) - it's worth checking how badly fragmented your disk is.  Another possibility is that your disk isn't using DMA - go into Control Panel / System / Hardware / Device Manager and check the advanced properties of your disk controllers.

Memory could be a problem if there are other system requirements, but VMS isn't very demanding in that area - I ran on 512K for a long time without it affecting previews.

It's worth noting that the preview has no effect on the rendered video - you can still produce good results.