It happens to me when lucid dream is crashing but I won't wake up but fall into sleep paralysis. When LD crashes, you lose your dream body aswell and then you are for few seconds absolutely without body. You don't sense any body + don't hear any noise,vibrations - absolutely nothing(well you can maybe have hallucinations sometimes) and then after few seconds you fall into SP. Interesting on this is that once(time before) I get stucked in this state for few minutes(of course I could wake myself up, but I didn't because it was interesting...something new ) I absolutely didn't feel any part of my any body(dream/physical/astral...) Maybe it's some deeper kind of sleep paralysis or trance(sleep paralysis is trance, not?) Have you experienced this state?