There's no doubt that 'X Factor' is absolutely brimming with talent. After last night's results show, the Fox hit is coming under fire for the most egregious offense a singing competition show should -- lip syncing. Who was guilty?

Well, everyone -- but Leroy Bell is the one who got busted.

The opening performance, a medley of David Guetta and Usher's hit 'Without You,' featured vocals from all remaining participants, and it sounded great -- but it didn't look that way. In a blink-and-you'll-miss-it moment, Leroy Bell's voice was heard without his microphone at his mouth or his mouth moving!

This is especially bad news for Bell, whose performance last week left much to be desired from judges and viewers alike.

After a slew of fan backlash, Fox addressed the accusations, telling TheWrap, "All survival songs are performed live, with just a backing track. For the group ensemble performance, the vocals are pre-recorded to allow acts to concentrate on preparing for their own live competitive performances on Wednesdays -- this is also no different to what other competition shows do for ensemble performances."

This isn't the only recent issue 'X Factor' has had to face. The show previously came under fire for conflicting reports on Dexter Haygood's exit (he says he asked to leave, they deny it) and ratings far below what advertisers anticipated.

This seems like a matter of principle. If you're hosting a singing competition show, the audience expects to hear people singing. If you're going to lip sync, don't deceive your viewers -- or don't get caught. This didn't end well for Milli Vanilli and it can't possibly end well for the fledgling 'X-Factor.'

Watch Leroy Bell Get Busted Lip Syncing on 'X-Factor'