Did people experience nausea?
I had the original APP on launch and the noise cancelling was excellent for me also at first, but after firmware updates it was not even close, like a fraction of its previous effectiveness.
However, the 'pressure' I felt sometimes was also reduced. So people had nausea from this pressure? It'd be a very un-Apple thing to do, but if they gave us a slider to control the amount of NC (like other brands do) then everyone could be happy. Hide it away so the default user never sees it, let those who want more noise cancelling push it up in Advanced Settings.