First thing to try is resetting the HR44 using the red button behind the front panel access card door. See if that helps.
If not, try using a different video connection as a test, such as Component Video (red, blue, green RCA cables), or Composite Video (yellow RCA cable). Do you see any video with either of these?
Also, just to be sure it's not the TV's HDMI INPUT, try using a different TV HDMI INPUT (if it has one), or try connecting a different HDMI device (your Bluray player?) as a test.