I was wondering of different babbling sounds and consonants come and go?

I was watching some videos of LO when he was around 9/9.5 months, and he was babbling a lot-dada, mama, gaba, baba, nana sounds were all there.

But now, at 11.5 months, he doesn't use most of those sounds, he mostly squeals, grunts, vibrates his lips, screams, etc. Every once in a while, he will say BA or GA, but not the continuous babbling.

Cause for concern?