WMP Classic... whats that?
there is WMP (Windows Media Player)
MPC Media player classic
lets assume WMP
what OS do u have...
i would suggest another player, Dolby audio license is ONLY allowed is Microsoft applications... we do a trick to disable the microsoft codec, and then FFDSHOW or ac3 filter cant take over...
check the video files, audio type...what is it... make sure that its set to use ffdshow for that codec...
or use MPC
but we need to know what OS u using, cause MS really enforces it in vista.win7
the video issue is very odd... video drivers
tell us MORE about your system!