Well I am away from home. Have a laptop and basic tools.
My mini quad working fine then decided to calibrate via the controller naze32 r6 the ESC. All seemed fine did not test fly it. And then travelled.
Arrived took off it flipped to the front right.
So I tried to calibrate the ESC individually by setting the rx to pwm. And throttle up power per down.3 of them when at low throttle double beep then single beep. One of them just double beeps.(missing the single beep the others do. I presumed it is not calibrated? I repeated several times. Always just double beep. Went back to one of the others. Double beep single beep. Any idea why. Anything I can do to fix it with a laptop and really basic tools? Thanks

Try with Blheli suite first and see if the application can read the ESC's and then try do a calibration with min_throttle 1000 and max_throttle 2000.

By "Calibrate" do you mean you used the motor tab to calibrate the ESC? or did you flash new firmware to the ESC's?

Try to go into BLHeliSuite, and check all the settings are the same on them, including PPM min and max first...