I have just downloaded the software and dragged and dropped a test track of my own while playing every few minutes a voice announces that this is a demonstration is this normal can it be removed ??
Thanks Dave 
Try downloading it from the authorized location: http://audacityteam.org/download/
You have either not downloaded Audacity or downloaded it fro a site that charges (or tries to charge) for it. From our own site the download is free and definitely not a demo.
WC
I am on a Mac OS X Lion 10.7.5 (11G63) I downloaded Audacity from the website version 2.0.30
Thanks Dave
That is not normal for Audacity. There is no demo version of Audacity, The official downloads are the full release version.
Details can be important. The current version of Audacity is “2.0.3”. There is no “2.0.30” version of Audacity, so if you really do have version “2.0.30” then it is not Audacity.
You can check the version number of Audacity by looking in the “Help menu > About Audacity”.
If “2.0.30” was just a typing error, then please tell us, did you download audacity-macosx-ub-2.0.3.dmg or audacity-macosx-ub-2.0.3.zip or something else?
No that was a typing error its 2.0.3 loaded from Audacity.source forge .net
Dave
So what happens if you record from somewhere, or even record silence, and then play that back - do you still get the “demo”?
What I’m getting at is maybe that audio file is suspect - where did it come from?
WC