I'm using a Microsoft operating system and I've lost all sound in both my German and my French courses. It's not my computer since I get sound with other sites. I'm hoping someone has a solution because I need to hear the pronunciation. (German is good; French accent is not so good, but better than nothing!)
First, ensure that your volume is turned up and that sound is working properly elsewhere on your computer. If the sound only appears to be broken in Duolingo's lessons, try refreshing the web page in the browser. If this does not fix the problem, try closing and reopening the browser.
I'm having the same problem. For me sound usually doesn't work on the first question. I get a pop up instead telling me sound is diabled. On the other questions sound usually works, but sometimes it takes very long to load. Today I haven't been able to get any sound at all. Also the whole site feels kinda unresponsive. Maybe DL is having server issues.
I'm not using a Microsoft operating system, but Linux and Firefox.
Edit: After clearing my browser's cache, sound is working again.