Yeah I think I had that a long time ago, but if memory serves me correctly it was with the Lowery subliminal product from Centerpointe (before alphasonix). I don't think it was the same Silent Stim tape although I have used that one too.
What I heard seemed like very faint voices; and yes, they would kind of drift in and out of my perceptual awareness. At the time I imagined maybe my mind was "hearing" the subliminal messages being decoded in the cerebral cortex (per the theory of high-frequency subliminals)-- maybe that's a stretch but I was in college at the time and probably in an "altered state" to begin with.
