How to trigger sound when rotation stops?

Hey guys,
I am working on my first game and hit a bump!
In the center of the screen is a disk that can be rotated by touching it.
The rotation angle is 45 degrees which means that the disk stops four times.
How could I trigger a sound when the rotation stops?
thanks
I am working on my first game and hit a bump!
In the center of the screen is a disk that can be rotated by touching it.
The rotation angle is 45 degrees which means that the disk stops four times.
How could I trigger a sound when the rotation stops?
thanks

Comments
When Attribute Self.rotation = (the angle that you want to make the noise could be 0-360)
play sound.
Also, I would love to place a smaller disk on top of the main one and rotate it without affecting the lower disk. Is this done with "layers"?
A little later, I will see what can be done ... I've spent most of yesterday creating artwork so now I have to make it rotate and do stuff