that means winmm.lib file in your library is missing you can either re-install the program or just download winmm.lib and paste in correct directory.
but there is another option for you. i.e. if you load the dll dynamically then you don't need library files. so try loading winmm.dll dynamically this might help you.
also make note that PlaySound cannot play sound file of large size may be greater than 1mb (i guess) in this case you can use function mciSendString........
give a try and if you couldn't do it reply to the post and i'm gonna help you....