How do I stop SurfaceGuis flickering?

Hey there. I have four SurfaceGuis placed on four different transparent parts, all of which are welded to the LocalPlayer's torso, and readjusted on the mouse's Move event to keep them in view. However, I've found that they flicker whenever the player jumps. The player is in LockFirstPerson at all times.

The SurfaceGui's parent parts are offset so as to occupy the four corners of the player's screen. If the player is looking directly straight, jumping does not cause the screen to flicker. However, pitching the view downwards results in the upper two SurfaceGuis disappearing. Pitching the view upwards causes the lower two SurfaceGuis to flicker. Looking at either pole causes all four Guis to flicker.

Has anyone else experienced this issue, and does anyone know how it would be best resolved?