Have you tried switching to PBR and back to DHS immediately. This can often resolve this graphical glitch which seems to affect some users.
If that doesn't help, try going to Shader Settings for each hair element and select the "Flow Map" channel. Now choose "Reset Texture" (see below). Does this reset to the correct colour?
Also do ensure your graphics drivers are up to date. Outdated graphics drivers can cause unwanted glitches with DHS.