I think it’s due to the constant sound pressure from the ANC - I used to feel very ill from the original quiet comforts back in the early 2000’s. Maybe my brain had a: “why do I have the sensation of sound on my eardrums but am hearing no sound?”

One long haul flight in 2016 I happened to have a pair of QC25’s available, and despite the sick feeling they always gave me, I decided to wear them - somehow over the duration of that flight I went from not being able to stomach them, to being fine with them!

Ever since then I have worn quiet comforts constantly at work and have had no problems! Currently have the QC45s.

So maybe try wearing the QC45’s in a VERY noisy environment to let your brain acclimatise to the feeling of the ANC while a little bit of outside noise still gets through - that might mitigate some of the weird: “sound but no sound” feeling?