The off‐resonance microwave absorption (subsidiary absorption) which frequently occurs at high‐microwave power and which may exist even in the absence of an external dc magnetic field has been used to observe the interaction between the magnetic flux reversal and the microwave loss processes in polycrystalline ferrite. These experiments have shown that the spin waves associated with high‐power, off‐resonance microwave absorption have a negligible effect on the flux reversal process. However, the flux reversal process has a marked effect on the high‐power microwave loss. During the flux reversal process, this high‐power, off‐resonance microwave absorption was found in some cases to be negligible.