A method of operating a control unit for controlling at least two different input fuel flows to a combustion device, e.g. a gas turbine includes the step of determining on the basis of at least one operating parameter whether the combustion device is in a predefined operating stage. In response hereto, generating a control signal configured for setting a ratio of at least two different input fuel flows to a predetermined value (psc1, psc3) for a predetermined time (dt) in case the combustion device is in the predefined operating stage.