First, you need to make sure the following items appear in your Wave Driver Opt-in List:

1. qttask.exe (C:/Program Files/QuickTime)
2. explorer.exe (C:WINDOWS)
3. IEXPLORE.exe (C:/Program Files/Internet Explorer)
3. any software you use to play streaming audio, including wmplayer.exe, winamp.exe, realplayer.exe, iTunes.exe, and so forth.
4. any other application (.exe file) you may wish to play through your hardware.

Also, make sure you press the "Update" button before quitting the MME Helper.

Make sure to select the Digidesign hardware as the primary driver for your application. For internet applications, go to Start > Control Panel > Quicktime, and select SoundOut to go to the Digidesign hardware. For system sounds, go to Start > Control Panel > Sound, Video and Game Controllers, and select the Digidesign Hardware. In other applications, the drivers may be
selected directly from the application.

If this doesn't work, sometimes restarting your computer will make the MME Helper start working.

Some (actually, very few) applications simply will not work with the MME Helper. However, there are no known programs that do not. It is largely dependent on your system (processor and chipset), software versions, and driver versions.