Importing MP3 Samples: silence automatically added

Hello - the first time I’ve had to post a question here, after using Audacity for over 8 years :slight_smile:

This time I really need help: I’m scheduled to lead an online workshop with 20 kids next week, teaching them to use Audacity to mix classical music samples with beats, field recordings, effects etc. I’ve done similar workshops for many years and have always enjoyed using Audacity for its intuitiveness and the abundance of good tutorials available.

Since updating to the latest version 2.3.3 last week, audacity adds 0.03 to 0.05 seconds silence at the beginning and 0.01 to 0.02 seconds silence at the end of every single mp3 sample that’s imported. It doesn’t add any silence to the imported WAV samples (see attached screenshots: 1 with MP3 file, 2 with WAV file, 3 with WAV and MP3s in a project).
If I “repair” the sample (removing the puffer silences) and export it as a WAV file, it comes out fine. If I export it as MP3, it “skips” at the loop edge. The sampling rate is set to default of 44100 Hz, 16-bit.
I couldn’t find any similar posts in this forum, so I’d really appreciate any suggestions how to solve the problem!!
Audacity 2.3.3
MacBook Pro (2012) using OS Sierra 10.12.6
Bildschirmfoto3 WAV und MP3 Spuren.png
Bildschirmfoto2 Rossini sauber geschnitten.png
Bildschirmfoto1 Rossini mit Pausenpuffer.png

MP3 is a very old format, and looping was not a consideration back in the days when the format was developed, thus the “encoder/decoder delay” was undefined. A consequence of this is that MP3s have a bit of “padding” at the ends. This is a well known limitation of the MP3 format.

The solution is to either use a “lossless” format (such as WAV or FLAC), or if you need to minimise the file size (and don’t mind about slightly reducing the sound quality), use a modern encoder such as OGG.

Use the program “Max” to batch convert your MP3 samples to AIF. Max properly removes the silence at the beginning and end.

– Bill