You can get funny results from playing with phase response settings. Theoretically it should not change anything as that would be determined by the filter in you DAC but, to my astonishment, if set, for example, minimum phase filtering, then you will get signal with no pre-ringing, great way to try minium-phase "sound".
That's what I got when recording the output from my WM8716 DAC with different phase settings. As far as I remember that's a 1kHz square wave and the only difference was phase response setting in SoX.
I had mixed results with intermediate settings, that is not very repetitive, but you know, it's really a great thing that you can control the phase response in your DAC from you PC.