In the mid-late 1990s IBM used this card in most of their Aptiva systems. Basically it did the work of a sound card and modem, but very differently than most cards of its day. It was similar to a WinModem in that the host computer had to load software onto the card for it to operate, but the MWave used a DSP instead of offloading the work to the host.
This seemed like a good idea at the time, but the DSP was no quicker than a CPU would have been when it came to doing things like playing music and using the Internet at once. The OEM version would support a 28.8 modem and cd quality sound, while the Aptiva version would do 33.6 with a software upgrade. The drivers for these cards were quite flakey and the cards themselves often failed due to their complexity.
It's also very annoying when you lose your driver cd and can't get online to get drivers since your modem needs drivers to get online and...