Bug - Huge performance drop when using PxVolumeCache(PhysX 3.3.4)

When I’m try to use PxVolumeCache it results in huge performance drop no matter how much objects are there in scene.

For example:
I’ve set up test scene with 7000 static and 1000 dynamic objects. Than I’m caching sphere with radius of 5 meters. It has 14 static and 2 objects inside. Caching takes 0.05 ms - it’s ok. Than doing 800 raycasts with PxVolumeCache takes 15 ms. But doing the same raycasts with scene takes just 3 ms! So it results in 5x performance drop.

The problem is in NpVolumeCache::multiQuery. When I replace code inside NpVolumeCache::multiQuery with scene raycast - I’m getting expected 3 ms.

After some testing I discovered that performance drop is present in case PxVolumeCache has more than 3 objects(no matter how much object are there in scene).

P.S. My CPU is Intel i5-4590 3.30 GHz.