A client device for hearing device communication, includes: a processing unit; a memory unit; and an interface; wherein the memory unit has a client device key and a client device certificate stored therein; and wherein the processing unit is configured to receive a connection response comprising a hearing device identifier via the interface, generate one or more keys including a certificate key based on the hearing device identifier and the client device key, and obtain an authentication message based on the certificate key and the client device certificate; wherein the processing unit is configured to obtain the authentication message by encrypting the client device certificate with the certificate key to obtain an encrypted client device certificate, and including the encrypted client device certificate in the authentication message; and wherein the interface is configured to transmit the authentication message.