I used nail polish in the leg and it still pops, but it's harder to happen.
I tried the same with my Ginyu but end up breaking his leg joint. I had to glue it back and lost the rotation articulation of the leg. Sad.
So, I just got my demoniacal fit jeice and it came with the problem in the left leg. Does anyone know any way to fix it? Maybe thickening the joint ball with super glue?