HDCP re-authenticatiing and causing a blink continues to be the lead suspect. Here's a test I can to that leads credence to that. Hook up with component video at 1080 and it rarely fails. Here it's perfect. Since HDCP is a dark art and companies won't open source and work together it appears we are in for a long wait for it to be perfected.
More at http://www.google.com/search?&source=hdcp&q=hdcp+blink