HDMI Hanshake Issue?

[DarenN]

Here's a stumper. I finally gave-up on my Samsung BD-1400 and bought the Panny BDP-35, which was a smart move; now all BD's play perfectly. Unfortunately, the Panasonic does a terrible job of upconverting DVDs, so I'm trying to use the Samsung for that purpose. I switched some inputs around, and now, when playing a DVD for 5-10 minutes, the Samsung always freezes on scrambled colors. Possible HDMI handshake failure? Even though it always plays for 5-10 minutes? Perplexing. I'd love to get an opinion on this.