How to get the Boombox, an older item for members:

Make sure you have the All Access Pass and go to the Town.
Enter the Dance Club, then go upstairs to the Dance Lounge.
Now go to the top of the Dance Club using the elevator.

Waddle to the box with 4 boomboxes in the left part of the room.

There’s a special dance if you’re wearing only the Boombox, try it yourself!