It's unclear exactly what you are attempting. Explain more fully step-by-step.
If it's a separate audio track, not linked to the video, lay it down on audio track 1. Then add video on video track 1.
If audio and video are linked, as with a typical video clip, and you don't want to affect the audio, UNlink them. Right-click either track and make that choice.
Use the current release. For licensed users upgrades are free for up to six months from purchase date. After that, VP will continue to fully function but a fee will be required in order to register the newest. Retain your old install file and registration info.