Denon 3805/3910 & DTS 96/24

[Dwight]

I have recently upgraded my system from Denon AVR1804/DVD1400 to AVR3805/DVD3910 and I'm having trouble playing DVDs with DTS96/24 sound.
I only have one disk in this format - Peter Gabriel 'Play' and when I played this disk on the old 1804/1400 system the audio would be downsampled to 48/12, not as good as 96/24 but still better than DD. But when I play it on the 3805/3910 sytem the sound is all but muted, I have to turn up the volume an extra 20db just to hear it.
When I press the 'status' button on the 3805 it shows the audio as being 96/24, so something must be amiss if the volume is dropped so dramatically. I suspect that it might be something to do with the player but I'm not sure how to check.
So I would like to know if there is a way of outputting 96/24 at normal volume, or how to downsample to 48/12 if that will output at normal volume. I can still listen to it in DD which sounds good, but DTS would be better. If there is no solution to this then I am a little surprised and disappointed that Denon would sell these supposedly compatible units and not have 96/24 fully implemented, or at least have the ability to downsample like the 1804/1400.
I have the 3805/3910 connected by D-Link 3rd, but have also tried coax with the same results.
Any help, thoughts, ideas, etc. are most welcome.
Regards,
Dwight