I'm not currently hearing any of the audio :( not sure if this is a site bug or an issue at my end?
Always look in the help page if you have a problem, but I copied it here for you: "My speech input is not working. What can I do?
Duolingo requires the Adobe Flash plugin to accept speech input, so first ensure that you have Flash installed. If Flash is installed but speech input is still not working, try refreshing the web page in your browser. If this does not fix the problem, try closing and reopening the browser. If none of these solutions work, make sure you do not have any browser extensions installed that would block the Flash plugin. Some extensions known to interfere with Flash include Ghostery, Adblock, Flashblock, and DNT."
Also try increasing the volume.
Check that: 1. Your speakers are on and properly connected. 2. Your volume is set to an audible level (check the values in Volume Mixer) 3. Your profile settings at https://www.duolingo.com/settings/account set audio on. Most likely not a site bug, probably your settings or your speaker.
I have taken my laptop to Microsoft store three times this past week! They fix the "problem" at their store/location; i.e., I can hear DL speaker either with or without headphones. HOWEVER, when I take computer back home, I still cannot get the audio to work in DL languages (French, Portuguese, Spanish & Italian). It's an unsolved mystery that is keeping me from moving ahead with my language learning skills!!