Thanks for the ideas, unfortunately they didn't solve the problem? The file extensions were already all in the same (lower) case and the file names in this case are all numeric dates, with hyphen separators. I previously tried re-uploading all the audio files, but that didn't change anything that I could tell. I can't see any issues with layers either, so for now, there still seems to be an unidentified compatibility issue between Xara & google chrome? I'll have to try the new "Edge" browser soon I guess....