Audio start time uncertainty

Questions & Answers
1

Hi,

I’m trying to write a game for my project, I’m doing it on Unity Android. My problem is that I want to play an audio in every second, but when I recorded the sound and analyzed it I found that there is some uncertainty in every audio’s start time (stdev: 0.035 sec). My main purpose is to give a pulse sound at the exact start of the game, this repeated sound is just a control for me that I can do it.

  • I used Fixedupdate function to play the sound in every 20th update
  • I used a very short .wav file (should I use mp3 instead?)
  • I recorded the framerate too, but have no found any statistical connection between the uncertanty and the framerate
  • If I adjust the fixed time step form 0.05 to 0.01 the deviation remains
  • I set the audio priority to max

I’m not sure that whether the time handling or the play causes this uncertainty.
Any clue or advise?

2

This happens because the way Unity uses FixedUpdate (see more here)

You could make the clip length exactly 1 second and play it looped. This way you won’t have play it again.

3

I tried several ways:

  • Using the method you suggested (to play a 1sec long file in loop) - better results, because time doesn’t change for 5-6 cycles, but then it does
  • Used Update instead of FixedUpdate and saved deltatimes between commands (audio.Play()) to a text file, I can’t find out why but the values based on time.time did not match with the recorded sound

Any ideas?