Whenever I try to make a music video or something similar, and add a music track to my timeline (in any video editing program) I come across a frustrating problem (which also happens to be hard to explain).

If I have say, 30 seconds of video clips and I add background music to it, and preview it from the very beginning, it will work fine. But if I preview it from, say, 00:15, the background audio won't be playing from the point it normally would (for example, it might be playing from what should be 00:10). This happens on all my video editing software, on both of my computers.

Any ideas?