I have been working with 6 audio files, about 12 minutes each, within Dropbox on my desktop computer. I have been annotating the files and it has all worked okay for the past few days. But suddenly last night it stopped working. The audio file opens up and the mark-ups to the audio show in the right-hand pane. But the file will not play. In fact none of my audio files play, even the ones I was not annotating. All audio within my Dropbox has failed.