I've tried this on both Sony Vegas 12 and 13 and it doesn't make a difference. I used Bandicam to record using x264 and it made an .avi video file. After following the instructions located at http://www.bandicam.com/support/tips/sony-vegas/ for the H.264 and PCM codec section, I went ahead and was able to open my .avi files in Sony Vegas. However, the preview video is horribly laggy and if I let it play for enough seconds the audio just quits on me too.
Things I've tried:
1. Changing the preview quality (even to draft on lowest settings) - did nothing but make the preview look worse WITH lag
2. changed project settings to a lower resolution - did nothing
3. tried with GPU acceleration on and off - made no difference
4. highered and lowered dynamic RAM preview max up to even 3GB and as low as default (200MB) - did nothing
5. changed external video capture application (which i'm sure has nothing to do with playback) did nothing
6. changed Preview device - did nothing
7. tried selecting a region and hitting Shift+B for better playback but this won't work for me. It only does it for a split second then quits. Either way I shouldn't have to select small portions to have decent playback.
The biggest factor here is that this is all taking place on a MUCH BETTER computer than my last one. And the last one handles playback JUST FINE! No lag or anything of the sorts. I have no idea why this would happen on a better build with overall better quality parts! I've done everything as I have on the previous PC and yet it still refuses to play correctly! When I look under Task Manager my CPU usage is only at 6% while all this lagging goes on too, so it's definitely not anything with my CPU. I have 8GB of RAM, so I know that can't be struggling since on my last computer I had 4GB and it was fine. It's also a 7200RPM hard drive. Sorry if I left out any other needed details. Please help!
What format are the files you are importing to Vegas?
Is the video you are importing a Vegas friendly editing format...?
If I import GoPro .mp4 files directly to vegas it lags badly... slowd down to between 1.9 and 6fps however if I convert in GoPro Studio to .avi (yes much bigger file but that changes when rendering) it doesn't lag at all.
Sorry... just re-read and realised you are already using .avi but of course .avi is the container and the data stored within can be compressed with different codecs. My GoPro .mp4 is converted by Gopro Studio 2.0 using CINEFORM codec and wrapped in an AVI container which is a nice easy intermediate format for vegas to work with
If you are using H264 codec for your bandicam recordings then you are producing files not unlike my GoPro MP4 files which also use H264 codec. This codec is complex and resource intensive and not ideal for video editing as it's difficult to preview at the original framerate. H264 is a great mastering codec to render the project to but not as an intermediary for editing because it's highly compressed.