Head making fizzing like sounds with movement

Hi all. I am not sure if this is anxiety induced but I've been having this strange fizzing / crackling like sound whenever i do the following movement. Bending over. Shrugging my right shoulder. Slight stretching of my back and neck. It all started when I fell asleep on the couch and woke up with a sore neck. Then there were episodes of dizziness that followed after for days. Went to see a GP and was told it was muscle related. Eventually, the pain subsided but the sound remains and now it feels like the sound is louder. And because of this, I've been gripped with finding out what is causing this sound. I've been to different doctors but was told as long as there's no pain associated, I shouldn't be too worried and say it's likely muscle related. ENT shows my ears are fine, hearing is fine. X-Ray of my spine didn't show anything unusual. Went for Physiotherapy and was told to do more neck strengthening exercises and to be more aware of my posture. So far, none have reduced the sound that sounds like it's coming from inside my head. The sound. It's similar to a rainstick / fluid rushing like sound when my movement is fast but if I move in a controlled manner, it sounds like marbles bouncing off tiles. Or poprocks? I've also been diagnosed with health anxiety which my psychiatrist thinks I'm being too fixated with my body sounds. But it's hard not to because the sound is just loud. And I also get this light dizziness whenever I hear the sound which seems to have occurred more frequently this year. Part of me thinks it might be something to do with something compressing my blood vessels to my head or possibly a tumour somewhere in my head. The one thing I recently discovered was when i press on a very specific muscle behind my neck, the sound goes away briefly. I'm thinking of getting an MRI done but my doctor thinks it's unnecessary at this stage because I do not have any other symptoms. So here i am hoping someone might have an idea what this sound is. It has consumed my life for the past 2 years and I am exhausted.