From your subject line, you're using the 5.1 analog input on the 950, which is good. Since you also have listened to DVD-A and SACD in the past, I assume that you are familiar with the discs you were listening and what you expected from them (since multichannel music is often mixed differently from movies as far as the .1 channel is concerned). What do you have the analog bass management switch set to on the 950's 5.1 analog input, and how is the bass management on the 5900 set up? Those two may be combining to mess you up somehow.

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