[djloche]

I've experienced similar issues using DisplayPort. I resorted to using Soundflower to properly route the audio - except that the problem persists in such a way that soundflower crashes at least once an hour. People experience zero problems on the same hardware running windows, so it is definitely a software issue.

For those thinking that it is as simple as picking the audio from the output list - that is the desired behavior. When you select your monitor as the output, the selector successfully switches, but your audio output is lost in limbo, or continues to play through the built-in-speakers of your laptop.

[vito]

Good to know I'm not alone there; sounds like exactly the same issue. For me it would happen with both Mini DisplayPort -> HDMI and HDMI -> HDMI (on the Pro).