I think I may have found the culprit.
So, I bought a new dvd player (waste of money) thinking the fault was with my dv600. I successfully connected the player to my tv, setup the connection. HDMI was working. This morning, turned on the tv, then turned on the dvd player... NO HDMI display
Did a bit of searcdhing on the web regarding this issue. The problem may be due to HDMI handshake.
Will try again later tonight. Based on what I've read on the web, turn on the dvd player first then turn the tv on.. Oh well..
Didn't want to 'retire' my dv600.. If this turns out to solve the issue then I have another Pioneer dvd player sitting around..