Ok im not sure how to go about reading the HTTP header's, but i have discovered something. Here is the first few lines of the m3u files that are passed to media player.

First a wma playlist that works from hijack V193:
#EXTM3U
#EXTINF:188,3 Colours Red - Pure
http://192.168.0.225/drive0/fids/dae0
#EXTINF:163,3 Colours Red - This is my Hollywood
http://192.168.0.225/drive0/fids/daf0

and one from v212 that doesnt work:
#EXTM3U
#EXTINF:188,3 Colours Red - Pure
http://192.168.0.225/3%20Colours%20Red%20%2D%20Pure?FID=dae0.wma
#EXTINF:163,3 Colours Red - This is my Hollywood
http://192.168.0.225/3%20Colours%20Red%20%2D%20This%20is%20my%20Hollywood?FID=daf0.wma

i tried removing the .wma extension from the url in the v212 playlist and it works fine. So looks like the extensions on the path after v193 are causing the problem. Seems strange tho that media player accepts the .mp3 extension, but is thrown off with a .wma one.