Comming back to the topic. The reason that many UPNP audio renderers is that most of the available products use chip sets from a few vendors which do not support gapless play and some other features.
Some vendors who develop their own solutions like Linn, Naim and I hope I am allowed to name our upcomming ENCLESO products as well, take care about the requirements of audiophiles and support gapless play, fast forward, etc.
Best regards,
Kai
www.encleso.com