DVD Audio Connections

My A/V receiver (Marantz SR 8200) does not seem to recognize the multichannel signal from dvd audio discs. The front panel of the receiver indicates that it is receiving only front left and right signals (although sound comes from the side surrounds).

I have only the coaxial out from the dvd player connected to the receiver, although the dvd player has separate outputs for each 5.1 channel and my receiver has inputs for 7.1. Are these the connections I have to make to get multichannel dvd audio signal?

My receiver does not seem to have any problems recognizing the various surround signals from regular dvds.

Any help will be much appreciated.