SDK Client is only compatible with the SDK server.
You cannot connect to a regular server using an SDK client, nor can the regular client connect to an SDK Server.
When using an SDK client you also need to create and host an SDK server.
It's up to you whether you want to create, host and use a standalone server or whether you integrate the server part in your (client facing) application and dynamically choose one client to also be the voice server and have the other clients connect to that client hosted server.
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