As far as my set-up goes. I am using an HD set-top box, a Sony receiver, and a Samsung DLP TV. The problem seems to be less persistent with premium channels such as HBO, but at times still occurs with those channels too. For example, shows on HBO such as Sopranos or Entourage are perfect. Newer movies seem to work fine too. But even on HBO, older movies from the 80's and 90's have the delay problem. Basic HD channels such as FOX, ABC, NBC, etc. all have the problem pretty frequently. Non HD channels also have the problem.
