I3dm tiles disappearing on camera move

CesiumJS
1

Hello!
I generated i3dm tileset (links to gltfs inside cmpt files) with road signs. Here is the tileset.json.

{
  "root": {
    "geometricError": 0.1,
    "refine": "ADD",
    "boundingVolume": {
      "region": [
        0.64246,
        0.96286,
        0.66265,
        0.97786,
        0,
        300
      ]
    },
    "content": {
      "uri": "http://localhost:8085/content/{level}_{x}_{y}.cmpt"
    },
    "implicitTiling": {
      "availableLevels": 8,
      "subdivisionScheme": "QUADTREE",
      "subtreeLevels": 4,
      "subtrees": {
        "uri": "http://localhost:8085/subtrees/{level}_{x}_{y}.subtree"
      }
    }
  },
  "asset": {
    "generator": "i3dm.export 1.0.0.0",
    "version": "1.1"
  }
}

After adding it to cesium (sandcastle, v 1.111) i have unexpected behavior (gif). On camera move features disappearing and appearing.
3D Tiles Inspector

What can cause this behavior? GeometricError was changed from 0.01 to 100 with no effect. Road signs are close to ground, but not under it.

How to make it visible in all camera positions?

Video