I so agree. There HAS to be a common thread. I googled "diaphragmatic flutters" and "injury to phrenic nerve" and "internal vibrations". They ALL refer to the diaphragm which controls the breathing. I also wore a heart monitor for 2 weeks to see if it would pick up anything and it did not. I got relief after a sleep study and didn't have vibrations for a week and a half after 2nd part of study where I slept with nasal piece. They slowly started coming back while I waited for my cpap machine. I didn't have them while using the machine but wanted to see if I could get same results as I did at sleep study so I started using it 4 hours each night, minimum required for medicare to pay, while watching TV on bed. I don't have the vibrations 90% of the time and I honestly think it's from having the air forced into my diaphragm by the machine. That's why I think mine is related to phrenic nerve injury. There has to be a doctor somewhere that find this fascinating enough to want to figure it out. When you can place your hand on your side or pelvic area or wherever the vibes are and actually feel the vibrations, that only proves they are real. My neurologist also thinks they may be from over active central nervous system. There's a lot of guessing going on but like I told him, I want to know what is PHYSICALLY going on in my body to cause them. Sometimes I feel them in my buttocks. They travel to different areas. I've been keeping a journal since 2019 and rate them every time I have them on a scale of 1-10. I thought one night one of my cats jumped on the bed but woke up and saw that it was me having vibrations, a level 10 that time. It is so crazy. I've not had covid or the vaccine. Please, will somebody out there help. I'm donating my body to science so maybe it'll be after I die they finally figure it out and it'll probably be something so simple........