Audacity Forum

It would be a pretty cool feature to have in Audacity. Being able to Flip The Audio/Notes, for example, this video: https://www.youtube.com/watch?v=PYQQrx-PxoQ or well it might just be a stupid feature but I like the thought of the feature being in Audacity.

I really want to know how to change the speed of a song in audacity while the audio is still playing like in this video https://www.youtube.com/watch?v=UePYQucCKMA the owner of the video was trying to help me but I didn't get it so please tell me how to change speed while it still plays'.