Please submit any iOS device calibration errors to us using this form. We will update our live database, and the errors will be corrected. After a new update has been received, reset your trim values back to the default, 7.0. To check calibration, compare our SPL Meter to a calibrated meter, using mid-band pink noise at a nominal level, such as 65-80 dBA. Make sure that AudioTools and your meter are set to the same weighting and decay. If possible, use A weighting and Slow response.