This appears to be a known issue with the Smooth Streaming SDK which the Player Framework relies on. We can repro this issue with a standard HTML5 video tag that does not use the Player Framework.

We have reported the issue to Microsoft and are eagerly hoping for an update that fixes this issue.

As you pointed out, a workaround for now is to organize your application so the control is hosted in the main HTML page (not in a fragment "page"). Another option is to host it in an IFRAME.

Workaround available: We recently discovered that if you set the source programmatically in the ready event of the page, it will work correctly. Setting it in HTML causes the problem. We've update our sample (included as part of the source download) to reflect this.