direct voice setup.exe

many solutions on net but none that work for me. most common is reg change
to direct /play /audio settings / change dword for duplexes blah blah
to values full duplex 3/////1/2 duplex 3/// mic recognition 2///.
tried many times still get message cannot run directplay voice setup.exe
check reg duplex changes and they have all been set back to 0//0//0//.
it is an asus k600a mb ac97 audio well known problem but have never found a solution that works not even disabling bios ac97 and installing sound card
same results when testing audio hardware??????