Could be imbalance whether muscular or structural.
Consider stretching/foam rolling/tennis ball rolling all posterior and anterior muscles of the lower body (includes bottom of the foot, calves, hammies, quads, adductors, abductors, abs/lower back, glutes). If you can identify problem areas, might give you an idea of what an imbalance is occurring.
But what Scott said also. Work barefooted. Might not be as bad as you think.. getting a vid up might be a good idea if it's particularly bad. Have any problems with mobility in like squats, oly, etc.?