There’s been bit of discussion (which is great) by user experience and web designers around how to use sound on a website
Including:
I was listening to some of the iWork tutorials on the Apple website and noticed that the volume of the narrators voice was different for each tutorial.
This meant that I was continually distracted and annoyed because I had to keep resetting the volume to a level that worked for me and others.
Usually what happens in this situation is that the user turns the sound off because it has become hard to use. Unfortunately the voice over was integral to the sales pitch… oops, sorry, tutorial.
Good bye sales pitch. Good bye customer.
Find the experience here.