Hi,
you're probably using Chrome 66, right?
Google has changed the units of the gyroscope values from radians to degree in that Chrome version.
That means all values are scaled by a ~57 factor (=180/3.14) and so the gyroscope is reacting way too fast.
As solution update to krpano 1.19-pr16 (or at least use the webvr.js and gyro2.js from there), this version is aware about that change in Chrome:
krpano 1.19-pr15 / pr16
Best regards,
Klaus