Crop MP3 to first 30 seconds

Question

Original Question

I want to be able to generate a new (fully valid) MP3 file from an existing MP3 file to be used as a preview -- try-before-you-buy

Answer 1

I have got an error while doing the same

Invalid audio stream. Exactly one MP3 audio stream is required.
Could not write header for output file #0 (incorrect codec parameters     ?): Invalid argumentStream mapping:

Fix for me was:

ffmpeg -ss 00:02:43.00 -t 00:00:10 -i input.mp3 -codec:a libmp3lame out.mp3