I believe that the only difference is that in Discrete mode, the bass is set at -10db but shows up as 0db to comply with some Dolby or THX standard; Cinema is the same but bass shows up as it should.

The question for me is, for a 7.1 system, if you leave it at Discrete/Cinema are you losing out on something. I have mine set for PLIIxMov. I no longer have my 598DP so I am connected to my DVD with a single coaxial connection. My 568.2MM automatically switches from PLIIxMov to DTS if I chose that output on my DVD menu; it automatically switches to EX when the soundtrack is so encoded.

Clueless as usual.

561, DSP5500s, DSP5000C, analog sides and rears