Nice post! While this probably sounds a bit strange, babbling in freefrom gibberish and stretching your mouth / jaw muscles can also help to relax sub-vocaliza

Nice post! While this probably sounds a bit strange, babbling in freefrom gibberish and stretching your mouth / jaw muscles can also help to relax sub-vocalization. It seems to relax an underlying vocal fidgetiness the same way a good stretch/workout does for the rest of the body. In other words, additionally approaching sub-vocalization as a physical phenomenon might be helpful.