Format of SoundBlaster entry point data structure:
Offset	Size	Description	)
 00h  3 BYTEs	signature "FB "
 03h	BYTE	driver major version number???
 04h	DWORD	speech driver entry point (see #03139)
 08h 24 BYTEs	???
 20h  ? BYTEs	data buffer for calling speech driver
		  (can be 117 bytes or more)