Unique issue with the Birdlocked and Dickcage devices?

I figured I’d give these two silicone gadgets a spin for fun. They both came equipped with 45mm base rings. The issue is that my testicles can slip out rather easily, often when I cross my legs or just move around normally. I considered trying the smallest ring size (40 mm), but it doesn’t seem like it would fix things completely. Has anyone else dealt with this?