As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DIVERTED DUE TO REPORTS OF THE CAPTAIN`S MACH AIRSPEED INDICATOR FLUCTUATING. SELECTION OF EITHER AIR DATA COMPUTER DOES NOT CHANGE INDICATOR FLUCTUATIONS. REPLACED AND TESTED THE CAPTAIN'S MACH AIRSPEED INDICATOR (MASI). SYSTEM OPS NORMAL.