The temperature dependence of magnetic susceptibility,x, of titanomagnetites (Fe_3−xTi_xO₄, 0⩽x⩽0.2) at different frequencies in the range of 13 Hz to 117 kHz is reported. Whereas the position of thex-peak of Fe₃O₄ at 120 K shows no significant shift over this frequency range, that of Fe_2.8Ti_0.2O₄ shifts from 70 K at 13 Hz to 115 K at 117 kHz. This seems to be the first observation of such large shift in the position of ax-peak observed at low-temperatures is attributed to the occurrence of an isotropic point (temperature at which first order anisotropy constantK₁=0) associated with change in crystal structure. In such a case a shift inx-peak with frequency is not expected normally. Thus, the observed large shift in the position ofx-peak with frequency is an unusual phenomenon and some of its repercussions are discussed.