Cannot drag and drop audio clip

For some reason I cannot drag and drop audio clips(mp3s or wavs) into audio clip slots. I’ve tried doing it both into audio sources as well as making a public audio script and dragging it into that. The audio clips won’t play in unity, opening a different program to play them when I open and their little thumb nail appears as pure white.

I used ubuntu 16.04, am doing the space shooter tutorial. Any help would be very much appreciated.

Fixed. Turned out I was missing avconv. Duh, silly me.