Los Angeles (E! Online) - The clubs won't be spinning Britney Spears' new single this weekend.

According to label sources, the official premiere of "Womanizer," Spears' first single off of her upcoming album Circus, has been pushed back due to an undisclosed issue with "the mix"—i.e., not Britney's vocals, per se, but rather how all facets of the track sound together.