Brought Back Memories
Messing around with a microphone and your siblings is tons of fun! Then she animated it, just to see what would happen. Flash authors release early material to the Portal to see if they can. Often, it is filled with spam, spam, spam, like what gets released through the Crews. This is an exception and is an actual test-run of the program and a work-flow.
The animation gets out of sync, a common problem. Maybe if the audio layer was set to Stream and you inserted blank frames throughout the mouth movements....
This Flash is one of those oddities where everything is improvised and done beneath a tight time limit. It's not brilliant, but now we know why "Canvas" (a later release) is so great.