I listen to Pandora as I walk to work and while I'm there, and as soon as an ad comes on, I turn the volume down to 0, then wait for a bit and turn the volume up by which time the music is back. This means a lot of ads they send my way I never hear what's being advertised. For instance, there's an ad that starts "Is your Internet, flabby, slow, and ..." and I always mute it before the sentence can be completed. So I have no idea what the product is, despite having heard the intro maybe a hundred times. Maybe I'm the only one anal enough to do this, but I doubt it.
So here's a free idea for you, Pandora. My reaction time is only around 2 seconds. Fortunately, that's still plenty of time to reach me. Consider this as a potential script you could pitch to your clients:
current song ends, load ad...
ANNOUNCER: Buy Coca-Cola, because it's good!
next song plays
ANNOUNCER: Buy Coke!
would work as well.
It doesn't take that long to make an impression!