We are currently working with Rhozet (http://www.rhozet.com/carbon_coder.html) tech support to help them tune their HLS preset. Their current preset works fine with the iPhone/iPad, but the Roku runs into trouble. We have found that different h264 settings cause the Roku to stutter during playback, however have not been able to pinpoint which. Does Roku have a definitive h264 advanced encode guide? Or does anyone know if there are specific settings the Roku has trouble with?