Forget about the "pro" stuff - it's only a matter of how the driver is designed, in the "old way" or the "new way".
Back in the old days before WDM was established (prior to Windows 98 SE), drivers could only handle stereo sound. If you had a card with more than one stereo pair, you needed a driver that showed up as multiple devices. Since WDM, drivers can be multi-channel (or "multi-speaker", call it what you will), and manufacturers can choose whether to offer one multi-channel device or multiple stereo devices. Both approaches have advantages - with multiple devices, you can use any software which is not able to address specific channel pairs, like Winamp, or the very early versions of mAirList, before I started to use BASS.DLL. The single-device approach allows you to handle multi-channel audio files more easily and without syncing problems.
And I'm not only talking about watching DVDs at home - if I remember correctly, the multi-channel MP3 standard has just been passed, and other file formats (including Ogg Vorbis and AC3) can handle it as well. Once the record companies start to produce more and more music CDs (or rather Super Audio CDs) in 5.1, it's only a matter of time until we have plenty of digital, surround-enabled radio stations on the internet or on digital terrestrial or satellite radio.
Regarding the error message: There was a bug in v2.1.16 which caused an Access Violation each time a player would go into Error state. This is why you got a message box instead of a plain "ERROR" display in the player. Now we only have to find out what is causing the error in the first place - the error code should be reported on the Details tab in the Properties dialog.
Torben
