New Line encodes some of their discs funny. The PS3 will only output DTS HD MA 5.1 on certain DTS HD MA 7.1 discs. It's not the PS3's fault, but the way the discs are encoded.

here is a link you can use to filter by audio type

http://www.blu-raystats.com/stats.php

just select DTS HD MA 7.1 from the audio drop down and click on filter. It will then show you all movies in that audio format, there are several.

Here is a thread that discusses the New Line encoding issue and which discs are affected:

http://www.avsforum.com/avs-vb/showthread.php?t=1017825

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