How to use metronome to 'sync' with an audio / video source

[DaafSamson]

Hi,

I was wondering if someone can help me along. I'm playing with metronome, hoping I can use it to (manually) align it with a media track (audio or video).

I can play both and play with the tempo in the metronome, but have a hard time figuring how to align them.

Let's say the beat (120bmp) starts at 4.5 seconds in my media track. how do I 'offset' the metronome to align it's beat and also 'start' at 4.5 seconds?

Any advice?