Center channel help

Hello,

I am quiet happy with my 2CH set up but with my HT I feel my center channel (VA Oratorio) sounds a bit harsh at near reference level.

I have calibrated my system with pre/pro (Rotel RSP1068) internal test tones at MV=75. Based on what I read in another thread AVR test tones are with dialnorm of -31 dbfs which should mean that a DTS sound track played at MV=75 should be at ref level.

Now I watched LOTR-ROTK-EE last night and I found that with my MV setting between 66-68 its ok. Above that it begins to sound a bit harsh from the center channel.

I have the floor covered with carpet and I have already set the dip switch on the back of VA to "warm" rather than "neutral" as to me this sounds better and blends better with my mains.

Now my questions are:

1) Is my performance expectation too much. Am I listening too loud anyway and its not a speaker real speaker limitation?

2) Is it because my amp (Aragon 8008BB) can't provide enough current to the center channel?

3) Is it my pre/pro either running out of juice or its sonically not good enough? For people who dont know 1068 I would like to highlight that one of its faults is that you need to set the speakers level almost at max to get decent output (too less volts IOW).

4) Is it due to the fact that my mains are going through a tube pre and amp thats making them sound more smooth/less fatiguing to be bearable at extremely loud volumes? If this is the case I was thinking about putting behringer 2496 eq with tube setting in the middle?

5) Is it due to the paper drivers on the VA? I read in another thread that normally these have higher distortion than other materials.

Any help or ideas are welcome.

Thank you