Bardin’s new masterwork pistol has the same audio bug that affects Kerillian’s spear and shield, as reported and acknowledged. When wielding the masterwork pistol, Bardin always makes the “heavy impact” noise regardless of the fall distance.
Just a small issue of polish with both weapons.
Additional note: Whenever you have the crank gun out, this same audio bug happens. Even a tiny hop up the stairs or a fall down from a table results in the maximum volume impact sound, as if your character had just fallen from a great height.
For a moment I thought that this might be a deliberate decision to emphasize the heaviness of the crank gun, but no, the comparably heavy drakefire gun doesn’t have this audio issue.
Only spear & shield, masterwork pistol, and crank gun suffer from unvarying falling noises. Every other weapon in the game uses different volumes for impact sounds depending on the height you fall from.