I have a 2013 mbp. With the latest Yosemite. and iTunes 12.0.1 i see this thing has a lot of 2 and 1 star reviews. And only one review for the latest version. And that review is a bad one. However the description of the functionality fits exactly what i wanted to a tee, that I went ahead and risked the 1.99$ anyway. What i wanted was an addition of functionality to iTunes… not a seperate app. It works exactly as i expected. Basically it allows me to listen to podcasts (which i have downloaded… not streaming) at 1.5 - 2x speed. It is not a seperate app. Its just added functionality to Itunes in an extra playback speed. It is an icon that sits in the task bar (up top) and has a selection of speeds. Thats it. easy peasy. I don’t notice any of the echoing or reverb other people have noted in reviews of earlier versions