Cross-connecting the audio between network 1 and network 2 forms a bridge between the radio networks over which the 
                                        2064 user can both monitor and communicate. The voice 
                                        bridge is automatically activated whenever voice is detected on either network.
                                        Audio levels are automatically adjusted and normalised via the 
                                        automatic gain control. Handset and speaker volume are controlled by the 2064’s volume switch..