Audio disappeared from project

[Kate5E33]

Hi, can anyone help me? I have a project with a mp3 audio track. It was all working fine but the audio has now disappeared in the source window and on my timeline. It just shows as a flat line. Does anyone know what has caused this and how to fix it? 

I've tried reimporting the file, changing my audio device settings and restarting Permiere Pro. Thanks if you can help. 

[R Neil Haugen]

Try converting the audio to a wav format in MediaEncoder, import that file and see if it works. PrPro isn't always "gracious" with mp3.

Neil