Headphone outputs are clipping

No where in the system is audio clipping.

My DAW is at -3db
If I adjust it to -6db the phones do not clip.
dspMixFx AXR - 0 channels are clipping.
dspMixFx AXR Meter shows nothing clipping.

The front display on the AXR4U shows clipping on PH. I can also audibly hear the digital clipping. No other audio measurement I can find has any clipping.

Turning the Headphones volume knob up or down does not affect the input, only the output so while turned down digital clipping still occurs. The only way to reduce the clipping of the headphones is to lower the DAW volume.

This seems very impractical, not correct. What to do?