How to control playback speed of iTunes U lectures in Mac OS?
It is currently not possible in iTunes. I highly recommend you to give feedback about this feature to Apple.
However there is a workaround:
- Download VLC
VLC is a free and open source cross-platform multimedia player and framework that plays most multimedia files as well as DVD, Audio CD, VCD, and various streaming protocols.
- Right click on the file in iTunes and choose "Show in Finder"
- Open the file shown in Finder with VLC
- In the menu "Playback" you can find the "Playback Speed" settings.