You don’t. You put it on your official blog/whatever and give people clear direction on where to find a good quality version. You don’t squash the excitement, and you seem decent for allowing people to listen for free.
“Make Some Noise
This wasn’t really part of the plan, but since this track is out there we wanted to let you hear it here first, or maybe second. Enjoy
The original link is now broken, so here’s the celeb-tastic video in full…