Magnavox MRV640 Owner's Manual page 33

The rear of the DVD Recorder features a DIGITAL AUDIO COAX OUT jack for connection
with a digital audio coaxial cable.
It can be used to connect the following devices:
Digital multi-channel sound provides maximum sound quality.
Consult the instruction manual of your receiver to find out which audio
formats it supports.
a
b The receiver does not support the digital audio format of the DVD
recorder. The audio format of the inserted DVD is displayed in the
display panel when another language is switched on. Playback using
6-channel digital surround sound is only possible when the receiver
has a digital multi-channel sound decoder.
Connecting additional devices