It was the music group, Milli Vanilli, that was stripped of their Grammy in November 1990 for lip syncing. When news media started to scrutinize the group's recordings, on November 12 1990, Frank Farian, a German producer and songwriter, conceded that Fabrice Morvan and Robert Pilatus (frontmen) did not sing Milli Vanilli's songs. They were not the original vocalists actually singing the songs. So, on November 19, 1990, Milli Vanilli was stripped of their Grammy. When the pair returned the Grammy Award, they hoped that the award would be given to the real vocalists.

Next, the group actually singing songs recorded a comeback album in 1998, but Robert Pilatus died before the album was released.

More Info: en.wikipedia.org