A system (10, 200) comprising: an input (11, 202) for receiving a line encoded data stream and an output (81, 204) for transmitting the line encoded data stream or an other data stream; a data generator (20, 206) configured to: receive the line encoded data stream from the input; generate the other data stream based on the line encoded data stream; and synchronise the other data stream with the line encoded data stream; reconfigurable circuitry (24, 212) operatively connected to the input (11, 202), the data generator (20, 206), and a controller (42, 214), and configured to: communicate the line encoded data stream to the output (81, 204) in a first configuration; and communicate the other data stream to the output (81, 204) in a second configuration; and the controller (42, 214) is configured to: make a determination, using the line encoded data stream, that a trigger condition is satisfied; and trigger reconfiguration of the reconfigurable circuitry between the first configuration and the second configuration, wherein the data generator is configured for synchronising the other data stream and the line encoded data stream by causing at least one property of the line encoded data stream to be preserved at the output (81, 204) by reconfiguration of the reconfigurable circuitry (24, 212). an input (11, 202) for receiving a line encoded data stream and an output (81, 204) for transmitting the line encoded data stream or an other data stream; a data generator (20, 206) configured to: receive the line encoded data stream from the input; generate the other data stream based on the line encoded data stream; and synchronise the other data stream with the line encoded data stream; receive the line encoded data stream from the input; generate the other data stream based on the line encoded data stream; and synchronise the other data stream with the line encoded data stream; reconfigurable circuitry (24, 212) operatively connected to the input (11, 202), the data generator (20, 206), and a controller (42, 214), and configured to: communicate the line encoded data stream to the output (81, 204) in a first configuration; and communicate the other data stream to the output (81, 204) in a second configuration; and the controller (42, 214) is configured to: make a determination, using the line encoded data stream, that a trigger condition is satisfied; and trigger reconfiguration of the reconfigurable circuitry between the first configuration and the second configuration, wherein the data generator is configured for synchronising the other data stream and the line encoded data stream by causing at least one property of the line encoded data stream to be preserved at the output (81, 204) by reconfiguration of the reconfigurable circuitry (24, 212). communicate the line encoded data stream to the output (81, 204) in a first configuration; and communicate the other data stream to the output (81, 204) in a second configuration; and the controller (42, 214) is configured to: make a determination, using the line encoded data stream, that a trigger condition is satisfied; and trigger reconfiguration of the reconfigurable circuitry between the first configuration and the second configuration, wherein make a determination, using the line encoded data stream, that a trigger condition is satisfied; and trigger reconfiguration of the reconfigurable circuitry between the first configuration and the second configuration, the data generator is configured for synchronising the other data stream and the line encoded data stream by causing at least one property of the line encoded data stream to be preserved at the output (81, 204) by reconfiguration of the reconfigurable circuitry (24, 212).