I've been working on a Flash script that allows the user to speak and playback what the user is saying after certain but exact time, say 10 seconds. That without sending anything to the sever, I've been asking around with no success about it. Is this simply impossible?
Yes this is possible, see here for an example of recording and then playing back the captured audio: http://help.adobe.com/en_US/as3/dev/WS5b3ccc516d4fbf351e63e3d118a9b90204-7d1d.html#WS184831AF-B842-4d52-BFB9-D7601F4A9E21
The example above basically does exactly what you are looking for.