fix mp3 with ffmpeg

issue: Sonos didn’t played back some mp3’s and showed an network related error message. At the same time Sonos could playback other mp3’s. So it was not a network issue.

solution: ffmpeg

1. macOS install ffmpeg in terminal

brew install ffmpeg

2. batch convert

for i in *.mp3; do ffmpeg -i "$i" "${i%.*}_fixed.mp3"; done

sources:

https://apple.stackexchange.com/questions/26099/is-there-a-way-to-convert-audio-files-in-mac-os-x-or-the-command-line-without-us#26111

https://stackoverflow.com/questions/5784661/how-do-you-convert-an-entire-directory-with-ffmpeg#33766147