Audio question on DENON DVD players 5910vs5900vs39

RE: 5900 vs 5910 vs 3910;
I use a Krell HTS7.1 via the digital Co-Ax only to decode ALL sound from my DVD player. Since these all have great pictures, I was wondering if there is any audio difference between the three while using an external decoder (Krell)?
If so, what is the difference, which one should I buy, and are there any other DVD players I should look in to? (I thought the Krell and Esoteric sounded a little better, but had less video features.)
Why don't you visit and look at the audio signal path mods available? It's possible to improve all three technically. Also, of course you know that HD-DVD/Blu-Ray audio and video is not decodable by any of these players. A future consideration. Lastly, the video quality of these players is not equal but the differences are based on connection and source material cadence types. Detailed evals are on the home theater secrets DVD shootout web pages. The 3910 has some minor image cropping issues over component cabling for instance that the 5910 does not. Just one example.

Using digital coax only, not analog connections and not IEEE-1394, for DD and DTS sound tracks, I've never understood how there could be any audible differences between players like these given DD and DTS is sent in packets.

I have seen arguments about why differences under these circumstance can exist, but these seem to be a minority opinion.

The above comment does not apply to CD sources, or to SACD/DVD-A which are not available over digital co-ax.