Recently, there was some speculation that BRITNEY SPEARS didn't sing her new track with WILL.I.AM. 

Now, "Star" magazine claims Britney doesn't even sing on HER OWN ALBUMS anymore . . . or at least, it isn't ALL her.

They talked to a guy named Murray Langston, who's the father of singer MYAH MARIE.  He claims she recorded seven of the songs on Britney's most recent album, "Femme Fatale".  He says, quote, "Myah can sound just like her.  She has a knack."

He adds that Myah was paid just $1,000 for each of the songs.  According to the Internet, Myah was one of Britney's background singers . . . so that explains her being on the payroll.

But Myah herself denies being more than that.

She reportedly says, quote, "I [had] the opportunity to provide background vocals for Britney on a small number of her most recent works, [but] I most certainly cannot take credit for her tremendous talent as a singer.

 She is a veritable 'living legend' with a longstanding reputation for excellence in all aspects of her artistry.  She is my idol and I have nothing but the utmost respect and admiration for her."

Britney's camp hasn't commented. 

(--Here's a YouTube video of Myah singing Britney's "Hold It Against Me".  And here's Britney's official version.)