Overlapping events sporadically happening when they always should

Does anyone else have problems with overlapping events only triggering part of the time? I am working on making 3d menus with sliders and other mesh objects for a virtual reality program. The menus are attached to above the left hand, and the right hand has a sphere attached to it that allows the menu buttons to be selected. When the menu button is overlapped with the sphere, the button changes color so that the user knows that it is selected. There have been a few problems with this:

  1. The buttons sometimes only change colors (meaning that they are overlapped) from certain sides, when the overlap settings are set to take collisions from all sides. This is very annoying, as the menu buttons need to be selected from the front and should be able to be overlapped from all sides. Some of the buttons only change colors when the button is hit from the back or one of the sides.
  2. Some of the menu components are sliders. When the sliders are overlapped, they are also supposed to change colors. In order to move the slider, one has to hold the trigger on one of the motion controllers (HTC Vive) and overlap the slider. However, the color does not change every time, even though it is clearly being overlapped as the slider is able to move.

Is anyone else having these overlap events sporadically happening in the software? The buttons and sliders should always change color on overlap, but it only occurs sometimes and from certain sides of the buttons/sliders, when we have checked to make sure collisions and overlap can occur from every side.

Thanks!