From YouTube: 'Song done in Burmese dialect featuring the klong yao (long drums). Performed in NUS on 23Mar07.'
At 00:15, you can hear someone hollering, 'Oooeeeeeiiii...', followed by a response from the rest of the ensemble. This is the call by the leader of the ensemble for the rest of the players to get ready.
Joker who spends his free time milling around NUS pretending to be a student...