PLC vs WI-FI stability (commercial use)

[KdsNext]

Ohh... Only now, when i started search about mesh network i found , that PLC needs adapters which i never bought )) So all this time, that speakers turned to PLC mode (in devialet app) they uses common wi-fi due disabled PLC network (right?)  . I assumed, that Devialet keeps PLC modules inside of speakers , something like dedicated channel through current wif-fi network.

Thank you Sir, 
Highly appreciated your idea!!!