When you import a music file, the conversion process can negatively affect the quality of the music. For example, playback volume may increase or decrease, compromising the sound of high or low tones. Make sure that the existing file associated with the prompt is cleared before you upload a new one.

To improve audio quality, before you import convert the audio file using an audio editing program. This example describes using the Audacity freeware program. 

1. Launch Audacity and open the audio file.
2. When presented with import options, choose to make a copy of it before editing.
3. Change the project rate to 8000 hz.
4. Change the volume to at least -10 db.
5. Export the file ( Export > Export as WAV ).

The file saves as type WAV signed 16-bit PCM.