With the current delivered version 1.1.1 there is an issue with request.dynamic and crossfade. Only the first crossfade will be made. It will not detect the next event.
https://github.com/savonet/liquidsoap/issues/98
The standard package for Debian is from 2013-MAY and does not contain the bugfix. Even the standard sources are shipping the buggy code. You have to use the latest developer sources from github (http://liquidsoap.fm/download.html#latest).
bytes and bones 