Try a different player & see if the problem persists. Might I suggest VLC: http://www.videolan.org/vlc/ (choose nearest mirror site) which has in-built codecs. If the problem is not there with VLC then it looks like your wmp needs an update of codecs. See the Upld/Downld Problems Sticky thread for a list of codec sources. If the problem however does still exist with VLC, then it may be due to a bug within LW's present version.