its not a lower standard. Its a matrixing algorithm. You are just fine, unless you want to matrix some rear speakers (6.1, 7.1) for which you will need PLiiX.
DD can be mono, AFAIK. 2.0, all the way up to 5.1.
However, I don't remember the last time I listened to DD, let alone DTS. By far, most of my HT enjoyment is with lossless codecs. Ok, there are a few that are DD+, but I think those are only HD-DVD within my colletion.
If your BDP, which you never named, is a BD-30, you cannot access the lossless audio since your Pio does not have the decoders. If you have a PS3, you should definitely be accessing them. Unless its one of those few models that only do video pass-thru with HDMi. I hate those receivers. Whats the point...
I am playing a Blu-Ray DVD, the audio is Dolby Digital 5.1. My receiver, a Pioneer VSX-918V-K, does not read the audio as Dolby Digital. Instead, it is reading it as Pro Logic II. I understand Pro Logic II is a lower standard than Dolby Digital. Any idea why my Pioneer receiver is not reading and playing the audio in Dolby Digital? Have tried playing with the settings and no luck.

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