i don't have a clue. I've been saying throughout, my testing is with xbmc; specifically the builds from here https://launchpad.net/~wsnipex/+archive/xbmc-fernetmenta-master tracking fernetmenta's dev branch of xbmc where the vdpau/radeon work is being done here https://github.com/FernetMenta/xbmc i guess if smplayer doesn't support vdpau mixer it can't test whether something's wrong with it.