mp3 not accepted by audacity

 in case you are trying to import an mp3 file with Audacity and it fails with error "incorrect filetype"

you can check it with the file command line tool in cywin/Linux/etc

$ file ./somefile.mp3

./somefile.mp3: Audio file with ID3 version 2.3.0, contains: MPEG ADTS, layer III, v1, 128 kbps, 44.1 kHz, JntStereo

$

after some googling it turned out that a simple fix is using mp3validate 

https://mp3val.sourceforge.net/

(binaries available for windows/linux/etc)

for Debian/Ubuntu you should be able to use a plain

sudo apt install mp3val in case you do want to proceed with fixing the file without creating  a backup you can simply launch this command: mp3val somefile.mp3 -f -nb and then boom - Audacity will be happy in importing it.