I've just got my PBO. Have no problems with initial setup and accessing it via network. But when I'm playing video it looks like HDMI connection is is got reset from time to time. As a result TV is "blinking" and right after that I can see TV screen resolution info on top of the video - this usually happened when I just connected my laptop via HDMI cable and TV set got recognized new video source. So it looks like TV(or PBO) is loosing HDMI connection and restoring it.
This is not TV/HDMI cable issue because when I connecting my laptop via HDMI with the same cable TV never "blinks" like that.