There are a number of occasions when the logger may issue a bleep:

  1. Reminding it is working and reminding you to select the trip type.
  2. You are moving before the instrument has established its satellite connexion
  3. The instrument lost its power
  4. The instrument lost the satellite coverage.
  5. The GPS antenna is damaged and not receiving satellite signal anymore.
  6. The instrument memory is full or almost full and needs to be deleted.   How to Erase data from the instrument 

What to hear what the sound are ?   Consult the sound samples here