Hi Andre,
Sorry to hear that you ran into this issue.
Since you mentioned that the audio stopped working after installing a recent update, can I ask if downgrading to an earlier version allows the audio to play again? And, are you accessing your course from a local directory when attempting to play the audio file?
If downgrading to an earlier version works, would you be willing to share a copy of your project file here or in private by opening a support case so we can take a closer look at what's happening? We'll delete it when we're done testing!
On the other hand, if downgrading doesn't work and this behavior affects multiple projects and audio files, try repairing your Storyline 360 installation to see if this fixes the issue.