An apparatus for generating an output signal includes a receiving system 160 generating a plurality of signals having a first format, an insertion module 166 inserting a source identifier into the plurality of signals, an encoder 182 encoding the plurality of signals into a plurality of transport streams and a multiplexer 210. A local area network 130 routes the plurality of transport streams to the multiplexer 210 to form a combined signal. A processing system 200 compares the source identifier to an expected source. When the source identifier corresponds to the expected source, the processing system 200 modulates the combined signal to form a modulated signal. When the source identifier does not correspond to the expected source, the processing system 200 changes the combined signal. A modulator 214 modulates the combined signal to form a modulated signal. A system 202 forms the output signal from the modulated signal.