Constant mmmmm sound

So my baby (5 months) has been saying mmmm sound. She used to say a lot of oohhs and ahhhss but for some reason all I hear now is mmmmm sounds. Even her cries or whenever she’s annoyed has turned into mostly mmmm sound. She smiles often and chuckles when we try to make her laugh (she doesnt know how to do a full laugh yet), and she always like make the motion that she’s like chewing something. I don’t know if she’s playing with her tongue or saliva when she does that. She perfected rolling from back to tummy on her right side and then going back too. I have seen her do it on her left but mostly on her right side though. I am wondering if this is something anyone else has experienced? I’m really hoping for some babbling again. I miss hearing all the different sounds and squeals she could make.