Give a stream of consciousness and then the final answer. Aida Yurijivna Nikolaychuk, sometimes spelled Nikolaichuk, (Ukrainian: ) is a Ukrainian pop singer and model. She was the winner of the third season of Ukraine's X-Factor TV talent competition in 2012. She drew special attention during the show's second season when judges interrupted her performance of Polina Gagarina's Lullaby (, Kalybelnaya), suspecting her voice was actually a digital recording. They challenged her to sing the song a cappella. Although visibly surprised, Nikolaychuk sang the song equally well without accompaniment.

Answer this question: x factor judges thought she was lip syncing?
To answer the above question, the relevant sentence is: She drew special attention during the show's second season when judges interrupted her performance of Polina Gagarina's Lullaby (, Kalybelnaya), suspecting her voice was actually a digital recording.
So, the final answer is Aida Yurijivna Nikolaychuk.