Fractional variability amplitude, F_var as a function of frequency for data simultaneous to the MAGIC observation periods (left) shown in Fig. 3 and long-term data samples (right) shown in Fig. 4. The F_var of the radio core (right) is indicated by an open circle, while the values computed for the components C1 to C5 are represented by filled symbols (C1: circle; C2: upward triangle; C3: star; C4: downward triangle; C5: square).