addressed File added, audio is from an older, discarded file.

[tedv19]

I added a .VOB file from a DVD of home movies. When I play it in Clip Preview, the audio is from a .VOB file I used in a previous project (never saved). I then closed VideoPad, removed the DVD, deleted temporary files, restarted the PC, reopened VideoPad, added the .VOB file, same result. Is the program leaving files somewhere on my PC that is causing this. Problem has happened multiple times, but previous starting over resolved it.

[borate]

When you "removed temporary files" did you go to OPTIONS | DISK tab and Clear Unused Cache Files?  Then close/reopen and repeat before loading anything.

What VP release is being used?  Try the latest and report back.

Share the VOB for inspection.  Upload the file/s to a free server, such as Google Drive or MS OneDrive, get a shared (public) link, copy the link and paste it here or to me in a Private Message via the mail envelope in the top-right corner of this forum.  When using Google Drive, if necessary change "restricted" to "anyone with link can view."

[tedv19]

Thanks, your suggestion to clear unused cache addressed the issue. I just downloaded VideoPad this week, so it should be current, V12.28 (which was also hard to find; need to select the right "Help" option). Obviously I am new to the tool. But I would say that playing the audio from a cached file with a newly-imported video is a bug. 

[borate]

Probably not a bug, but cache corruption, which happens rarely.  It's good practice to clear the cache prior to beginning a new project.

Don't clear it if simply reloading the last project worked on or the cache will have to be rebuilt.

Clear Unused Cache Files can be used at anytime during editing.  Save time by not loading files that won't be used in the project.

For protection, Save Project File AS routinely, giving it a unique # or name, so as not to overwrite prior saves.  Using Save Project Files (no AS) will overwrite.  From the HOME tab, that choice is available by clicking the chevron to the right of the Save Project button on the toolbar.

The latest 64-bit version, recommended for lengthy, UHD and complex projects, is linked above.  The home download page is here.