I'm not the DOSBox expert, and I haven't been able to find anything about your problem with Fable using a Google search.
The closest I found in the DOSBox support washttp://www.dosbox.com/DOSBoxManual.html#Stutter
SOUND: The sound stutters or sounds stretched/weird.
You may be using too much CPU power to keep DOSBox running at the current speed. You can lower the cycles, skip frames, reduce the sampling rate of the respective sound device, increase the prebuffer. See section 13: "The configuration (options) file"
If you are using cycles=max or =auto, then make sure that there is no background processes interfering! (especially if they access the harddisk) Also look at Section 10. "How to speed up/slow down DOSBox"
If that doesn't help and no one here has another suggestion, maybe try posting at the DOSBox forum.http://www.vogons.org/viewforum.php?f=53