First noticed this under the audio settings, if you change values then click "Reset" without clicking "Apply" it doesn't actually reset any of the sliders.
Audio tab:
No sliders are reset
Video tab:
Doesn't reset VSync or Resolution options
Controls tab:
Doesn't look like anything on this anything on this tab gets reset. I only tried a subset of the keybindings but none of those I tried actually reset. This screen seems the most crucial for the reset to work.
Gameplay tab:
None of the settings on this page reset either.
