Silent Killers

This is another GP incident which took place in tuition. GP was late to class, and we were all waiting outside. Ashwin(aka jash) asked madhu for his mobile to play games. GP arrived in a few mintues, and we went inside the class. Jash then returned the mobile to madhu, and madhu put it in his pocket after changing it to silent mode. Vinay entered the class late, and sat next to madhu. Kailash, who was behind vinay, whispered something to vinay, which madhu ignored. All of a sudden, the verses, "Swoing in the rain....i am a swong in the rain...", tore through GP's lecture, and madhu realised that it was his mobile which was ringing. He immediately cancelled the call, and apologised to GP saying that he had switched it to silent mode, and promised that it wont happen again. Madhu could not understand what was going on. GP got angry and asked madhu to get out. Madhu replied saying that vinay was the one who called him. GP got even more frustrated, and asked both of them to get out.
Outside the class, vinay confessed that he DID call him, but jash and kailash were the masterminds behind the whole strategy. It seemed that kailash and jash had changed the settings in the silent mode, and only then had returned the mobile to madhu. So, after the class got over, while madhu was explaining to GP about what had happened, he received another call from B, the mobile as loud as ever.