video audio keeps going when gone to another frame

[AngusBeef]

This seems like it should be obvious, but something is odd about this.
I have a row of buttons that go to different frames and plays a video.
The same button bar is at the bottom through the whole thing.
So, if you press button 1 to goto frame 20 and play vid1, the vid plays fine.
But if you press button 2 to goto frame 30 and play vid2 before vid1 is done playing, the audio continues to okay and nothing stops it until it finishes the entire thing. You can still see and hear vid2, but the audio of vid1 is still going.

Any ideas?

thanks