Imported Files dont work?

I have the 1.2.5 version on my mac and for some reason it doesn’t play any imported files. I’ve tried changing the format to mp3 ect. it doens’t seem to do anything. Any advice?

Audacity 1.2.5 is obsolete.
Unless you are running an ancient version of OS X I’d suggest that you upgrade to Audacity 2.0.2 http://audacityteam.org/download/
To add support for additional file types you can install FFMpeg:
http://manual.audacityteam.org/o/man/faq_installation_and_plug_ins.html#ffdown ,