DAC to DVD problem...

I have a Audio Alchemy DAC with Jitter interface. These are connected to a Argon DVD player (SPDIF Coax).

When playing CD the lock indicator turns on and everything is fine. The problem is when the CD stops. After some time the DVD player shts down and the lock indicator turns off. Then there is some digital noise in my speakers...very naste....

What can I do?