In the first member device 120, the first communication circuit 121 is arranged to operably receive and transmit various Bluetooth packets. The first cypher key generation circuit 123 is arranged to operably execute various selected or predetermined cypher key algorithms to generate cypher keys required by the first member device 120 for conducting subsequent Bluetooth data transmissions with the Bluetooth host device 110. The first control circuit 125 is coupled with the first communication circuit 121 and the first cypher key generation circuit 123. The first control circuit 125 is arranged to operably generate various Bluetooth packets to be transmitted by the first communication circuit 121, and arranged to operably parse various Bluetooth packets received by the first communication circuit 121 to acquire related data or instructions, and further arranged to operably control the cypher key generating operations of the first cypher key generation circuit 123. In addition, the first control circuit 125 is further arranged to operably adjust the clock signals employed by the first member device 120, so as to synchronize a piconet clock utilized among the first member device 120 and other Bluetooth devices.