Start button sensitivity issue.

THANK YOU. I wanna buy you a beer. I was just about to return my watch and holy ***. this worked! You just saved me tons of time.

GARMIN THIS NEEDS TO BE ON OFFICIAL SUPPORT PAGE.

We Garminites must look out for each other. Garmin did come through to me with a fix for this one but overall, the 8 is a big PIA.

I agree! It's first Garmin device and the experience is not something I was expecting of such a premium device. Fingers crossed for quick fw updates!

Could you please explain how you create such a txt file when using a Mac, and Android File Transfer. I have created said file in MS Word for Mac, and saved it as KEY_CALIBRATION.BIN and it saves it as KEY_CALIBRATION.BIN.txt and all the variations don't work when uploading it.

You need to either save the file without an extension or rename it afterwards and delete the extension.

Ok, got it to work.

MacOS users, use Text Edit and when you open a new file, change in setting, the preference to plain text and then make sure, that add txt radio button is not selected. Save as KEY_CALIBRATION.BIN. making sure to keep the dot at the end. 
When using the MTP program (Android File Transfer App) make sure to put the file into the drive, not any folder. It's habit to drop it into the Garmin folder, as that is what we used to do when updating firmware, don't!