12/13/2012
Expired: 
Yes
AP: 
0
XM: 
0
Discovery: 

Thumbnail icon on the investigator board is an audio spectrogram.
Clip contains clicks/knocks and electronic synthesizer musical notes.

Solution via D.J. Harbaugh on Google+:
Using Sonic Visualizer software, a “melodic range spectrogram” was loaded. Changing the zoom produces this image: