Sound cards - do they play back all bytes?

I use Aduacity for recording tracks from records and cleaning them up. I Know Audacity has a click/pop remover, but I haven’t worked out the settings in this, and I often find it easier to locate them myself and remove them using ‘Repair’. My problem is this: sometimes I think I’ve located a click, but then I play the section again and it doesn’t seem to be there. I know clicks can come from electrical things switching on & off in the house - if this happens during playback, the click will only be heard once. But sometimes, it seems like the click is there, then it disappears, then comes back. Is it possible that the sound card is not playing every byte of data; sometimes playing the click, sometimes not? I am posting this question here for 3 reasons:

  1. Chasing down sound clicks using a program like Audacity is probably one of the few places where this would matter,
  2. I would think there are users out there who would be knowlegable about this,
  3. I can’t think where else to post it!
    Can anyone help?

I don’t think this matters in this case, but: Windows XP, Audacity 2.0.0, Intel Core 2 duo, sound driver is actually on the Asus P5K mother board (that may matter).

If you play only a very short section of a track you may notice that the very start or very end of the track may not actually come out of the speakers. I’m not sure exactly why this is, but it appears to be a peculiarity of some sound systems (possibly something to do with how the audio data is “buffered”). If you play a track all of the way through then it should play all of the data (with the possible exception of the first/last fraction of a second).

Clicks can sometimes be produced on playback by interference from within the computer, such as hard drive activity.

Thank you. :smiley:

I realized that appliances in the house could cause clicks, but I didn’t know that things like the hard drive could.
That’s probably what’s happening - at least it seems like a reasonable guess.
Things in the house don’t turn on and off very much, but the hard drive… the computer is always accessing the hard drive! :exclamation:
Stupid thing! Anyhow, that seems like the most reasonable guess.

Regardless of the source of the click if it exists on the actual digital recording you should always be able to see a spike in the waveform when you zoom in using the magnifying glass icon.

However, when you are zoomed in very closely and hit the play button time is highly compressed, and the click or pop is almost certainly going to be indistinguishable. Therefore to check the click zoom back out again and start playback 4-5 seconds earlier.