Diva Gwen! Stefani A ‘Nightmare’ To Work With On ‘The Voice’ Season 12

Staffers on the set of The Voice are already fed up with returning judge Gewn Stefani, an insider told RadarOnline.com —

and the season hasn't even started yet!

“Gwen has been butting heads with so many people,” a source close to production told RadarOnline.com.

Stefani, 46, started dating Shelton, 40, in 2015 after they both went through high-profile divorces last year. And even though Stefani was replaced last season by Miley Cyrus, she is back with a vengeance!

In a newly released preview clip, Stefani is seen telling a potential team member, “I just did a country song. With Blake Shelton. I got the hookup!”

Shelton quickly snapped back , “That is so inappropriate to talk about us hooking up!”

However, as RadarOnline.com reported, Stefani and Shelton are getting paid big bucks to put their love affair on full display! But staffers are getting sick of it, the source said.

“Sometimes Gwen seems like a completely different person that she used to be before she and Blake became super serious,” the source told RadarOnline.com.

“She used to be everyone’s favorite and now a lot of people can't stand her because sometimes she acts like she owns the show and they are lucky to have her.”

Do you think that ‘The Voice’ fans are getting sick of seeing Gwen Stefani and Blake Shelton’s love fest? Tell us your thoughts below.