I last seen this problem months or years ago, but yesterday I saw it again.
On a Orbiter install with OrbiterSound and DG-IV (2014 update) during DeltaGlider-IV rollout after landing, I have multiple G-Excess warnings and the ship is not braking.
Sounds like the old problem with graphics clients giving too high FPS for vessels to touch the ground properly. Are you using the DXD9 client? I vaguely remember Jarmo fixing that some time back, though I could be wrong.