Playing back a wav file will work fine. If you want to be able to change the message by changing a text string rather than re-recording the wav file, you can use Microsoft Agent (http://www.microsoft.com/msagent/default.asp) or AT&T Natural Voices (http://www.naturalvoices.att.com/). I have used the first two methods with LabVIEW but not the third, but I will investigate it for my next voice project because the AT&T voices sound better than Microsoft Agent voices.
