Time remapping audio clip with Adobe CS5.5?

Im trying to time remap a short audio clip. The effect I want to create is that a song is playing on a record player and the power plug gets pulled. I want the song to play normally then gradually slow to a stop.

I've tried recording the song through my camera's microphone so it would be attached to video, then tried time remapping in Premiere Pro. The audio didn't time remap, but the video did.

I imported the song file into After Effects, but I'm so new to the program I can't figure out easy things like how to get the sound to work after an effect is applied, or how to even move keyframes in the graph. I've searched at length to find answers to these simple things, then gave up.

I have Adobe Audition too, but don't see a way to time remap on it either.

I've looked on the internet for hours and hours trying to find a tutorial, thinking that surely someone has tried this effect before, and I can't find anything. All I can find is how to change speed overall, not gradually.

Can anyone point me in the right direction? Do you have a forum to suggest for me?