Some people probably already know this but I discovered this by accident and it's pretty useful.

I always use the mouse wheel to zoom in and out of the timeline. This morning, I couldn't do it. It just kept scrolling up and down all the tracks on the timeline and when the mouse was placed over the timeline cursor I got a Speaker Icon and could shuttle with audio back and forth depending on my mouse move speed.

Seems the CTRL key was stuck in on the keyboard!

when the mouse was placed over the timeline cursor I got a Speaker Icon and could shuttle with audio back and forth depending on my mouse move speed.
Lucky you! It doesn't do this for me. I wish it would.

Vegas 7.0e

Have to say it surprised me! As the shuttle/scrub control using JKL keys give poor audio! This one is much better!