I heard this too. I looked at WBRU's Tunegenie, and there were no songs listed as being played during that time. My best guess is that perhaps their main computer was down, and they were playing music off of a back-up hard drive or even CDs that were not Tunegenie encoded, and wouldn't have the trigger points set to go from one song to the next, therefore leaving the dead air between songs. It did sound very 'college radio' for a while.
Jacko