No Audio w/ Audio Sink

I am running Ubuntu 14.04 and just got GRC up and running.

I have made the sketch seen in this youtube video

GNU Radio Tutorials: Part 1 - GRC, Sources, Sinks, Audio & GUI Blocks - YouTube

but I cannot for the life of me, get the audio sink to work.

Everything seems to be running just fine, but I can’t hear a thing
though my speakers.

Any help would be much appreciated.

Thanks,

Zack