If you are using Tubbler you may have a timeout issue after the movie is playing for a short time.
We have tried everything to address the issue but did not come to a positive result. For now it looks that no matter if we are using WebView or the new WKWebView in Yosemite the problem still resist. I hope that Apple can provide some help. I have already opened a Technical Support Request and await positive response with the instruction what we have to do.
Sorry for the inconvenience. I will keep you up to date…
We have released Tubbler 1.7.1 which should address the problem.