I'm not getting any speech. I am getting the congratulatory "ding-ding" when getting a question correct though. I'm getting sound from youtube too. I've restarted my computer thus reopening my browser and duolingo but still getting the same problem. If it helps, this is occurring at the Portuguese "Possesives" Lesson 2.
Hi! Try removing/disabling browser extensions. Some tips for how to do that in specific browsers:
Chrome - http://support.google.com/chrome/bin/answer.py?hl=enanswer=113907 IE - http://windows.microsoft.com/en-us/windows-vista/internet-explorer-add-ons-frequently-asked-questions Firefox - http://support.mozilla.org/en-US/kb/disable-or-remove-add-ons#w_how-to-disable-extensions-themes-and-plugins
Also, what is the current version of the browser and flash you're using? What is the result if you use a different browser?