I'm using Spectrum 96 white glass and having no luck with getting rid of the devit! I've reduced the upper temp to the point where I'm just getting little more than a tack fuse and cleaned the surface very thoroughly. The amount of devit was less than previous attempts but still apparent. I'd quite like to be able to have a better fuse but this means a higher temp and more devit! Anyone else have this problem the the white glass?