I was always dissapointed by the last 2 Dr. Brain games (discounting the later later ones altogether).
That said, I assume it’s another audio buffer error! Since the timer patches, this seems to be the only error left unsolved.
I don’t know which file DB3 uses, but a file called ‘resource.win’ or ‘sierra.ini’ or something created by installation should exist. Could someone post their contents of it (right-click, open with Notepad) and paste here?