When using a *-control channel, openHAB acts as the actuator, so you will receive commands but you can’t send commands to the knx bus. The only thing you can send to knx is a status.
Type switch-control:controlSwitchHueStehlampe "Hue Stehlampe" [ga="1.001:2/2/0+<2/2/1"]
openHAB will receive commands from 2/2/0 and from 2/2/1, but it will send status updates only to 2/2/0. openHAB will NOT ask for a status at startup, as openHAB holds the status itself (openHAB is the actuator), so please omit the <
Type switch:switchMusikzimmerLicht1 "Licht Musikzimmer" [ga="1.001:2/2/0+<2/2/1"]
Now what? you’ve got a real knx actuator at the same GA? That’s ok for the command part, but not for the status GA. Sending a status you have to define an exclusive GA for each channel (in the meaning of switches, dimmers and so on)