Falling Through Floor after a certain number of Triggers...

Hi,

I have a ground plane as normal and a character controller attached to the Main Camera. I also have some objects floating in mid-air (around eye-level) which are each composed of six quads facing outwards to make a cube. (I do this because I want to be able to easily detect which face of a cube was clicked on, as well as apply different flat textures to each face of the cube.) I have set these quads to be marked as Triggers, so that the player can walk through them (which is what I want), but still be able to click on each individual face.

These cube objects are also aligned onto a 3D grid, which is also floating in mid-air. This 3D grid is made up of a series of unit-length cylinders and small spheres at the cross-over points between these cylinders. All of these spheres and cylinders are also set to be triggers (there are various things that I need to do with these as well, but again I want the player to be able to walk through everything).

When there are one or two of these composite cube objects inside a 3x3 grid, the player can walk through them just fine. However, when you reach three or more, when the player starts walking through them, he also falls through the floor and sort of (bounces) just below the floor, then when you carry on walking past them you appear back up on the floor again. The same effect seems to occur even if you have none of the composite objects but just a larger grid (i.e. with lots more triggers).

Is this just an inherent problem with using lots of triggers? Is there a way around this?

Thanks!

TL;DR: When walking through lots of triggers, the player falls through the floor. Is there just a cap to the number of triggers Unity can reliably handle?