According to one embodiment, an apparatus has first and second connectors configured for removably connecting to one another. The first connector circuit has a first differential amplifier, a first differential signal path, a first capacitor section capacitively coupling the first differential amplifier to the first differential signal path, and a first DC biasing circuit for imparting a first DC bias to the first differential signal path opposite the first capacitor section. The second connector circuit has a second differential amplifier, a second differential signal path, a second capacitor section capacitively coupling the second differential amplifier to the second differential signal path, and a second DC biasing circuit for imparting a second DC bias to the second differential signal path opposite the second capacitor section having a different magnitude than the first DC bias when the first and second connector are not connected. One or both of the first and second connector circuits is configured for detecting a change in the first or second DC bias and outputting a connection status signal in response to the detected change.