“[Julie] has always been very hands-on as the host,” a source close to the the network’s reality competition show tells PEOPLE. “She knows everyone’s name on the crew, and she is very involved. She’s been doing this show for 18 years; she’s the face ofBig Brother. A lot of the crew members are millennials who grew up watching her, and she has been so great to them. She’s very approachable, and she really cares about making the show as good as possible.”

“The last few weeks have been different, though,” the source adds. “She comes in, does what she has to do, and leaves. She doesn’t make small talk; she doesn’t talk to the crew. She comes in, does her job, and leaves. It’s clear you can’t approach her. If she’s not on camera, she’s either on her phone or she retreats to her room. It’s like a different host. It’s not that other people can’t host a show like this, but I don’t know how you get someone who cares as much as she does. It feels like she’s totally checked out ofBig Brother, which makes everyone nervous.”

Reps for Chen andBig Brotherdid not immediately return PEOPLE’s requests for comment.

Last week, Chen, 48, returned to CBS to hostBig Brotherand sent a subtle message of solidarity to her husband as she signed off from the show, looking at the camera and saying, “I’m Julie Chen Moonves. Goodnight.”

Sonja Flemming/CBS

Big Brother

It was the first time that she has used the last name Moonves on the show — and it came just days after her husband was fired after multiple women accused him of sexual harassment.

A insider close to theBig Brotherproduction previously told PEOPLE, “Everyone knows that it’s a big ‘f— you’ to CBS that she did it, because she never, ever refers to herself as anything but Julie Chen.”

Gary Gershoff/WireImage

2016 CBS Upfront

“It’s sort of perfect when you think about it,” the insider continued. “The casual viewer probably didn’t even notice, but I promise you that the network did. They were watching every single second of the show to see if she would do anything. They must have been breathing a sigh of relief because the show was almost over, and then that happened!”

Chen announced herdecision to leaveCBS’s daytime seriesThe Talkon Tuesday, saying “Right now I need tospend more time at homewith my husband and our young son.”

While Che continues her hosting duties at theBig Brotherhouse for the time being, her passion for the show and the competition has not seemed the same, according to the first source.

“She always used to be involved in every part of it,” the source says. “She wanted to make sure that the show didn’t get stale. She doesn’t give any input now, and hasn’t for a lot of the season. It’s ‘Stand there, look at the camera, say your lines, go home.'”

“She’s a complete professional, but she’s just not as hands-on as she used to be,” the source adds. “It’s very different. It really does feel like she’s done. This season is almost over, but we don’t know anything about what will happen next season, and it’s making us all very nervous. It’s all we talk about.”

Chen and Moonves married in 2004 and share 8-year-old son Charlie.

source: people.com