Hey FyreFiend, I just register to this forum to thanks you!!
I have the similiar exact problem, except it's start with loud high pitch buzzing sound for few days. Then this host error and waves control panel won't appear.
I did exactly as you describe, uninstall realtek driver, uninstall and reinstall SoundBlaster X-Fi MB and re-install driver from the CD, it solved my problem.
I wonder if it's okay to update the Realtek driver now, because Dell has release latest Realtek driver at support website.
Now, tomorrow Dell technician will visit me with new speaker for replacement. Guess I'll get a new speaker for all the hassle. :P