An MRI system (100) is proposed (for generating one or more images of a body-part of a patient under analysis); the MRI system (100) comprises an injector head assembly (155), for injecting at least one medical fluid into the patient, having a clock unit (340) for providing a clock signal with a clock frequency. The MRI system (100) comprises means (420-425; 445-460) for adjusting the clock frequency in response to a manual command and/or to a detection of a degradation of the images. An injector system (155,165) for use in this MRI system (100) is also proposed. Moreover, a corresponding method (500) for managing the injector head assembly (155) is proposed. A computer program (400) for implementing the method (500) and a corresponding computer program product are also proposed.