just looked at the starter project and there appears to be a difference in the scripts between the starter and the webvr version. The starter project works fine but replacing them with the plugin files on github breaks the Cardboard functionality and removes the use fullscreen attribute.
This is going to sound odd but I dropped the files from the starter project back into my cardboard app and now I can click on the screen and get stereo images which is great but now the sound has stopped working. It works fine on the desktop but no sound on cardboard. Strangely though I have other projects which I built from the starter kit which have sound and work fine.
And before you ask I removed the sound file, recoded the file to ogg then added it again to a different entity. Again it worked on the desktop but failed on Cardboard.
I think I am just going to lie down in a dark room.
I replaced the sound file from one cardboard app with another one and the sound started playing again.
So it looks like webkit on Chrome will only decode certain sound files and not all of them and since it didn’t really matter what format it was .ogg or .mp3 the only thing I can think of is the length of the sound file. It was quite a long music track so perhaps there is a limit to how long a track can be on mobile chrome vs desktop.
Anyway I have stopped looking at the problem now. I think I will just get in the habit of building two versions , one for Vive and one for Cardboard and keep them seperate.