Mute button, please help

I am just retruning to flash from cs2 and its much, much harder.
I want to create one simple mute button. Does anyone havea link to how I can do this from start to end in cs4?

Everything I’ve found ends with me getting the error message:

“Current selection cannot have actions applied to it”

      while tutorial carries on and neeer address this as a possibility.

What am i doing wrong?

Very fustrated.