The only references I could find on google talk about the audio device being set as "removable disk n".
Another possibility is that the device simply hasn't been assigned a drive letter. You could try assigning it one:
start>control panel>administrative tools>computer management>disk management
If the device is listed there, right click on it and choose "change drive letters and paths". If a drive letter is listed there you have your answer. If no drive letter is listed, click Add>Assign the following drive letter, and choose a letter.
Also, while you are replying, attach a screenshot of the My Computer window (showing the audio device). And if possible, post a screenshot of the properties window(s) of the device.
-genius_at_work
