Need help with older Pioneer Receiver

[Vargas01]

Ok, I have an older Pioneer receiver with no HDMI inputs so I have been using the optical connection from my samsung BDP-1500 and I've been enjoying movies with no problem (dark knigh, underworld 1 and 2, pinapple express) but recently I have rented two movies from blockbuster that will not play the audio through my receiver. They are:

Wanted

Max Payne.

I checked and the audio track on both of these titles is the DTS-HD audio and there is no choice to select "DOBLY DIGITAL 5.1". This is weird though because both TDK and Underworld will play the HD audio track on my receiver, it just isn't in HD (I understand this).

Am I just screwed here or is there some setting I am missing?

Help. All has been fine until Blockbuster has gotten involved. Also, if this is how all new Blu's are going to be (only with the HD audio and not the dolby digital) I will have to upgrade receivers.