According to 教育部國語辭典, 戲謔 (traditional characters) should be read as "xì nüè". However, according to 新华字典, 戏謔 should be read as “ xì xuè”. Why there is such a difference and why you might think you heard of "xì nüè" is because, "戏謔" was be defined to read as "xì nüè" once before. After some years, the P.R.O.C. changed the sound back to “ xì xuè”, so you still can hear two different pronunciation.