I don't think there is a way that has worked for the masses, to completely stop/avoid subvocalization.
The more you practice SuperReading & Dipping, the easier it becomes to keep your awareness on the top half of the words in a sentence, and moving through the upper area of each word just slow enough to recognize the word and meaning, but fast enough where you don't have a chance to start subvocalizing.
It's okay to subvocalize during Rapid Reading. But as soon as you feel you've gotten what you need from the page, or the material seems to begin repeating itself, pick up and keep moving forward.
