avr 430 question and help......

I have bought a refurbished avr 430. I have paradigm cinema 90's up front for the left and right speakers, and they sound great. However, I have just received and hooked up a paradigm cinema cc for the center channel, and it just doesn't sound right. I have the left, center, and right speakers all set to the same tone; i.e. they are all at +8. The sound from the left and right channels is clear and just about perfect. However, the sound coming from the center speaker is sort of dull. The sound is sort of muffled when coming from the center speaker; i.e. the trebble doesn't sound as clear or as precise and the vocals sound a little on the muffled side. This occurs when the avr is in all modes; logic 7, dolby, theater 5, tv, radio, dvd, etc. Even when I lower the the left and right speakers to +4, the sound is even throughout, but it the sound is still mushy when coming out of the cinema cc center speaker. Oh, when I flip-flopped the left speaker and the center speaker (i wired the left speaker into the center amp and the center speaker in the left speaker amp), the cinema cc center speaker (now the left speaker) sounded perfectly fine and the left cinema 90 speaker (now the center speaker) sounded mushy and lacking the high's and clarity it once had when connected to its left speaker amp. And I have checked the polarity of the speaker connections, and they were all correct.


I hope that wasn't to confusing, but I don't understand why the cinema cc center speaker is sounding the way it does when connected to the center amp. It sounds perfectly fine when hooked up to the left channel amp.


I was hoping that you all might have some suggestions or have had some similar experiences as I?


Please help. Thanks for your time.