Voice Memo recording giving problems with lip-sync

Hi everybody, 

I am trying to do lip-sync in Adobe Animate with a recording which is originally done with Voice Memos on the iPhone. I have exported this Voice Memo recoding with audition as AIFF en WAV mono en stereo and nothing seems to work. The Voice memo recording is originally mono.

(I have to work with Voice Memo recordings until I get the professional recordings from the client)

Thanks for your help!

Cristina