Inspection procedure 14: The Initial Check Sound Of Hydraulic Unit Is Loud: Notes
WARNING: This page is about a different car, the 2012 Mitsubishi Lancer. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
When installing brake tube, match the axial center of flare nut and brake tube with the center of hole at the hydraulic unit side, and check that the fluid does not leak.