Well, I think I've got this all fixed now... I'll try to explain what I did in hopes that it may be of assistance to someone else.
I believe I had two problems:
1. The 'no items to display' was caused by the wrong profile for my TV.
2. The failure to play some videos was caused by the wrong version of ffmpeg.
The details:
1. To fix the first problem I could select the correct profile for the TV from the drop down list, but what I did finally was to changed the "config/profiles.xml" this way:
"<X-AV-Client-Info>.*BRAVIA KDL-.*</X-AV-Client-Info>"
this is probably a more blunt fix than is necessary, but I tried the suggestion above and it didn't seem to work for me. Now serviio recognizes my TV and I no longer get the dreaded 'no items to display'

2. The failure to play some videos (mkv, mp4, mov) was caused by the wrong version on ffmpeg (I believe). I'm running ubuntu 11.10, when I turned on the debug level of the serviio logs, I saw an error message pop up when I tried to play one of these videos. It said something about ffmpeg exiting with an error, so I tried to copy and paste the command 'manually' at the unix prompt and got an error from ffmpeg that said "Unknown encoder 'libmp3lame'". This seemed odd to me because I have libmp3lame0 installed. I recalled I had another problem with another app that used the mp3 encoder. I seem to remember some sort of controversy from the debian community if the mp3 encoder was 'free' (free speech not free beer) and I had to install it from another source. So I did some web searching and found the place I once got this from is now called
www.debian-multimedia.org so I added to my sources list the following:
deb
http://www.debian-multimedia.org testing main
actually I used synaptic, but it ends up in the /etc/apt/sources.list file.
Anyway, after doing a resync I had a bunch of updates, one of which was ffmpeg... I can't remember the old version number, but the new is 0.8.5-0.0
after I did this and the upgrade there were a bunch of dependency problems... missing files, which I had to add separately. I think if I was going to do it again, I'd remove ffmpeg then reinstall the new version. The other strange thing is that it seemed to uninstall my vlc I have not reinstalled it, yet, I was waiting until I was sure the serviio problem was fixed.
I think that's about it...
thanks to everyone that made suggestions to my original problem and thanks in advance to anyone that would like to suggest a more elegant solution
