How to isolate analog ground

[FartingNoveltyToyEngineer]

I am working on new version of a bluetooth speaker layout. Previously i made a cut to the ground plane in effort to isolate the dac section from all switching noises but
i now realize this might have been a bad idea. So how to do this better? How bad this kind of practice is in terms of EMI? Attached is a sketch which shows where all
parts are going to be located and screenshot from the old dac layout/upper right corner. Thanks!

[thm_w]

You have a signal crossing the cut on the left side, which is not good.
Can you show top and bottom layers.

youtube.com/watch?v=vALt6Sd9vlY

youtube.com/watch?v=icRzEZF3eZo

[Doctorandus_P]

Splitting GND planes has been deprecated for 10+ years. (Nearly?) always it's better to a single big GND plane combined with physical separation between the "noisy part" and the "sensitive part" of the PCB.