Unknown

From MetaGeek Friend:

I take dance lessons at a dance school. At each dance nights they
organize, the WiFi doesn't work! The computer is connected to it, but
no access to the Web. I record the following during one of those night.
And then, tada! A BIG spike at approx 2433 MHz. During a dance lesson,
no spike of any sort in this area (I took a record during mine), and so
the WiFi works without a problem. Any ideas of what it could be?