Mariah Carey looked as beautiful as ever performing "#Beautiful" with Miguel and Young Jeezy Sunday night at the BET Awards in Los Angeles, but once again viewers are questioning if she was singing live or lip-synching.

The latest accusations come just a bit more than a month after her reps denied lip-synched a medley of hits on the finale of "American Idol."

We reached out to Mariah's reps at PMK and they didn't have any immediate comment on the controversy.

Prior to her performance, Nick Cannon told E! News that Mariah keeps it real during her performances and it's "all her." He added, "My wife is a perfectionist and clearly because she's done it right all her life. She actually puts a lot of work into these performances."

However, plenty of observers on Twitter don't agree. Here are some of the tweets questioning Mariah's performance.

What do you think? Were Mariah's vocals live or pre-recorded?

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