Problem when exporting to MP3, sound files no longer play at proper times

Hi all,

I am new to audacity and have run into a bug I can not figure out.

I want to have a voice clip play every 30 seconds or so. I arranged the sound clips and spaced them all apart to the time I desired, and when I preview it in audacity it works fine. However, when I export the file and play it with VLC as an mp3 the specifically timed intervals no longer play at their desired times they all seem to by off randomly by about 10-20 seconds.

So when I play my mp3 file there is no sound at the 30 second intervals as seen in the attached screen cap they are all off except for the first one.

You mean that the voice clips, rather than playing at roughly 30s, 1min, 1m 30, 2min, 2m 30… , they play at 20s, 1min 10, 1 min 20, 2min … That badly off? If you play it twice, are they “off” by the same amount as the first time, or does it change each time you play it?

What about that other (drone?) sound? How does that sound?