I think the AC was noisy. Same case with Sreeshant , his hotel AC was too noisy. But he is a clever guy, he knew if any murder takes place in the next room , he will not hear & he will be balmed & will be unable to play cricket. So he fought with hotel staff for change of room where AC was not noisy. Sometimes in houses there is full scale robbery (TV , DVD players , jewellry is robbed) and the residents dont wake up coz they are in deep sleep. So how can you assume the parents heard anything.
