Hh, my immediate reaction is that if the main problem is dialog clarity in movies and there's no problem with music, you should check the VP180 carefully to make sure all drivers are operating. You might even disconnect the other speakers(keeping all settings the same)and listen to the center alone.

A correctly calibrated setup would be too loud at 0 for most listeners during movies. If you mean something like +10 on the 4311 volume control is needed, then yes, something's wrong.

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Enjoy the music, not the equipment.