Ewe .wma music... convert them to .mp3 at a similar bitrate, problem solved.
There is no nice way to achieve this with .wma, other than using Silverlight, we will not be creating a Silverlight player for a long time. It is the very last thing on our to-do list.
The Windows Media Player plugin is glitchy in other browsers than IE and will not achieve your dynamic playlist like RAWR-Player.