=(

I am practicing japanese and since a week I am not hearing a voice pronounce the words.

Have you checked if you have muted?
On the site, check the speaker icon in the upper part of the site.
If on IOS check your mute button if it is a Ipad and if other check the mute button. Double click the home button and swipe right till you get to the sound icons. In the app it self you can go to settings and check if you by mistake have turned off sound or taken down the volume. You can also go to the device settings and check your sound settings. Sound do work fine for me in both Chinese and Japanese apps and sites.

Also, if you're using an iphone, make sure you didn't press the mute switch above the volume buttons.

No, I am using skritter through a computer and the speaker isn't muted. =(

Well..judging by other topics it was a bug. But it's fixed and I have sound again. =)