As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ATB - ON CLIMBOUT LT & RT MACH POINTERS STUCK AT 260K IND. ALT SYS NO CHANGE. RETURNED TO SDF NORMAL AIRSPEED. FOUND VMO AND MMO SWITCH IN ALTERNATE POSITION, PERFORMED ADC CHECK IAW AMM 34-12-00-6 LT & RT, OPS CHECKS GOOD. PLACED VMO MMO IN NORMAL.