Mariah Carey performed on Saturday night at the 2015 Jazz and Blues Festival and demonstrated how NOT to lip sync. 

First she mixes up lines, forgets the words and then almost gives up towards the end.

No doubt she seemed to be having issues with her in-ear monitor. 

Watch the fail here!

Skip to 45sec to see where it all unfolds. 

Want more? Here's one of our fave moments from Jase & Lauren – they’re always up to something! Weekdays from 6AM on KIIS 101.1!