What would cause your FM transmission audio to be distorted on voice peaks?

In an FM (Frequency Modulation) radio system, the loudness of your voice directly dictates how wide your radio signal deviates from its center frequency. If you talk too loudly or hold the microphone too close to your mouth, this frequency deviation becomes wider than the receiving station's filters can handle, causing your audio to "clip" or sound heavily distorted on volume peaks. Talking louder would obviously only make this problem worse. An inverted repeater offset would prevent you from hitting the repeater at all, rather than causing audio distortion. Finally, transmit power only affects your RF signal strength, not your audio clarity; increasing transmit power just makes your distorted voice reach further.