At 0:24, fans started to chant when Sungmin’s part in Our Love was played. Then after that, everyone caught the idea to chant so that Kyuhyun would get distracted.
And it worked! Kyuhyun, upon hearing the “Saranghaeyo Lee Sungmin” for the first time, paused and smiled a bit. Then he continued to speak though he was a bit stuttering. Then, when fans started to chant “Saranghaeyo Lee Sungmin” for the second time, he was able to finish the word Saranghaeyo, then he paused to hear ‘Lee Sungmin’, then he laughed for a bit. He was actually startled and he could not remove his smile anymore.
I thought Sungmin was the one who could not concentrate when he thought of Kyuhyun? It looked like Kyuhyun could not concentrate on doing anything whenever he thought of Sungmin.