do you have a large collection of soundfonts which are superior sounds? from my experience years ago with soundfonts, they were typically better sounding than some of the GM softsynths like Roland Soundcanvas (or even Coyote, IMO), however there are better alternatives now such as SampleTank, Kontakt, many many others. even TTS-1 has better sounds than a lot of the soundfonts I used years ago.

You've gotten great advice above on how to get your soundfonts to work, but I would advise "breaking out of your soundfont shell" and see what else is available today! you will probably be pleasantly surprised!