I can split one large mp3 file into several files based on silence using the mp3split command / program below
mp3splt -f -t 4.0 -a -d split audio_file.mp3
You need to set the
-o (output format) option.
Try something like:
mp3splt -o @N3_@f -f -t 4.0 -a -d split audio_file.mp3
001_audio_file.mp3, 002_audio_file.mp3, 003_audio_file.mp3…
The man page is a little messy, but it's all there.