Embodiments relate to a filtering device that filters a telecommunications signal and outputs to a telephone and a data port depending on whether a data plug has been inserted into the data port. A micro switch at the data port is activated and brings filtering components in-line when a data plug is inserted, and the filtering components filter the combined telecommunications signal and outputs filtered telephony only signals to the telephone port, and data only signals to the data port. When no data plug is present in the data port, the micro switch is not activated, and the filter is bypassed, thereby presenting unfiltered telephone and data signals to the telephone port as well as any extension sockets connected thereto, but no signals to the data port.