Can't do lessons in iOS
Most of the type-what-you-hear lessons on level 22 in iOS are totally silent and cannot be completed. Otherwise the sound is fine.
Okay, forget I said "level 22." Clicking on a roundel results in silence, but the sound effects are still working. I am not in the tree, I am way past that in the practice exercises, which means there is no way to know what "skill" is being tested. There is no oral input, so stating things is pointless.
The type-what-you-hear practice exercises are all silent even if I click on the blue circle. That means I am completely prevented from finishing the course.
In short, Duolingo stopped working yesterday.