Certain models of Suunto’s D6 and D9 wrist
computers have a significant software bug that
may cause them to track time incorrectly. The
error may occur when the computers automatically
recalibrate to the correct time, or when the
user updates the seconds in set mode. Suunto
estimates these models will malfunction 0.6 percent
of the time (one out of 167 dives). When
the error occurs, every fourth second is not registered
during a dive and surface interval. The
computer shorts both the dive and the surface
interval by 25 percent. An hour dive would show
as 45 minutes, an hour surface interval as 45 minutes.
The error could seriously affect decompression
requirements.
The products affected are: D9, serial numbers
  62102582 and below, and D6, serial numbers
  62103693 and below. The serial numbers are on
  the back of both devices.
 A Suunto spokesman said says there have
  been no injuries, but a diver should immediately
  return the unit to his dealer who will send it
  to Suunto. There is no charge and turnaround
  time should be less than two weeks. Suunto will
  also replace the battery and perform a pressure
  test free of charge. At www.suuntoservice.com/safetynotice/diving, Suunto promises that the
  computer’s logbook memory will remain intact
  after updating; however, download all data onto
  a computer as a back up before returning it. If
  you don’t have a dealer nearby e-mail the Suunto
  Help Desk at SmauuntoD9-D6@nordictelecenter.fi.
  Or call 1 800 543 9124 in the USA and Canada.
  A computer with the correct software will bear a
  small white dot on the rear.  
A Suunto spokesperson told Undercurrent that
  the company is providing the free update for
  computers purchased through gray marketers
  such as Leisure Pro.  
The U.S. Consumer Products Safety
  Commission has been informed.