If the audio is the same on both sources, stack the tracks one atop the other. Right-click on an audio track and SYNC AUDIO. Videopad will match them up.
If there's a single audio source, but video on the same clip needs to be dealt with independently, right-click on either track and UNlink audio and video.
Then the audio track can be locked so editing on other tracks doesn't affect it. Right-click to the left of the audio track and Lock Track.
There's a feature that enables easy switching between video tracks: Multicam Mode. Access it via a right-click in the preview window, then click Preview Mode.
