Well, it might not be the problem (your blank recording that comes back doesn't really fit the pattern) but HDMI is a problem with every device out there. TV and A/V receiver manufacturers don't follow the specs closely and thus there are thousands of "HDMI 1.2" or whatnot out there. Making a receiver like the HR20 or the PS3 compatible with all of them is nearly impossible. So much for standards.
But HDMI is a good place to start in troubleshooting. A reformat or full reset may do the trick if it's a software glitch and then you can move on to HDMI if that doesn't fix it. I'd go over to DBSTalk and look up VOS (Very Old School). He is an expert on doing this and is willing to help just about anybody.
Honestly I haven't seen this blank problem reported much at all since early this year so it's not a general bug or problem, just probably something specific to your box.