Where's this noise coming from?

[ame="http://www.youtube.com/watch?v=TzAlSF2djZQ"]http://www.youtube.com/watch?v=TzAlSF2djZQ[/ame] Sound in question starts around 0:16

[ame="http://www.youtube.com/watch?v=RQSjeyzVzgA"]http://www.youtube.com/watch?v=RQSjeyzVzgA[/ame]