A driver circuit comprising: a rectifier circuit configured to receive an alternating current input voltage and to provide a rectified AC voltage (ACrect); a switching converter circuit coupled to a light source including a first set of solid state light sources comprising one or more solid state light sources of a first color and a second set of solid state light sources comprising at least one additional solid state light sources of a second color, the switching converter circuit configured to provide a direct current output to the light source in response to the rectified AC voltage (ACrect); and a mixing circuit coupled to the light source and including a switch circuit configured to switch current through the first set of solid state light sources in response to each of a plurality of consecutive half-waves of the rectified AC voltage (ACrect), while current flows through the second set of solid state light sources, the driver circuit being characterised in that: the switch circuit has in operation a conductive state and is coupled to the first set of solid state light sources; wherein the driver circuit further comprises a controller circuit configured to provide a controller output to change the conductive state of the switch circuit in response to each of the plurality of half- waves of the rectified AC voltage (ACrect); wherein the mixing circuit further comprises: a voltage reference circuit configured to establish a reference voltage; wherein the controller circuit is configured to provide the controller output in response to the reference voltage and the rectified AC voltage (ACrect); wherein the mixing circuit comprises a synchronous oscillator circuit configured to provide an output at a frequency of the plurality of half -waves of the rectified AC voltage (ACrect), and wherein the controller circuit comprises an operational amplifier having an output coupled to the switch circuit, a first input of the operational amplifier coupled to the output of the synchronous oscillator circuit, and a second input of the operational amplifier coupled to the reference voltage. a rectifier circuit configured to receive an alternating current input voltage and to provide a rectified AC voltage (ACrect); a switching converter circuit coupled to a light source including a first set of solid state light sources comprising one or more solid state light sources of a first color and a second set of solid state light sources comprising at least one additional solid state light sources of a second color, the switching converter circuit configured to provide a direct current output to the light source in response to the rectified AC voltage (ACrect); and a mixing circuit coupled to the light source and including a switch circuit configured to switch current through the first set of solid state light sources in response to each of a plurality of consecutive half-waves of the rectified AC voltage (ACrect), while current flows through the second set of solid state light sources, the switch circuit has in operation a conductive state and is coupled to the first set of solid state light sources; wherein the driver circuit further comprises a controller circuit configured to provide a controller output to change the conductive state of the switch circuit in response to each of the plurality of half- waves of the rectified AC voltage (ACrect); wherein the mixing circuit further comprises: a voltage reference circuit configured to establish a reference voltage; wherein the controller circuit is configured to provide the controller output in response to the reference voltage and the rectified AC voltage (ACrect); a voltage reference circuit configured to establish a reference voltage; wherein the controller circuit is configured to provide the controller output in response to the reference voltage and the rectified AC voltage (ACrect);