Son- Mum V1 3x3 cosmetic issue

[unirox13]

I've had my 3x3 Son- Mum cube for a couple of weeks now. I've solved it a few times and it's a really fun puzzle. However, out of the box it had a cosmetic issue that is finally bugging me enough to ask for some advice about. The corners have some fairly sizeable gaps between them and the edge pieces. It seems to be more prominent in certain places of the puzzle as well. For example, on the green face, g/o/w, g/w/r, and g/y/r corners have obvious gaps. But the g/o/y corner has no gapping. When you turn the green face, the same pieces retain their gaps. The gaps don't stay in those specific corner locations, just with the specific pieces. This leads me to believe that it's an issue with the pieces themselves, not with the core of the puzzle.

It doesn't have any effect on the functionality of the puzzle, it's merely an annoying cosmetic issue. I've taken a couple of the faces apart individually. Because of the complicated internal workings of the cube, I couldn't really see any problems.

So, here's where you guys come in. Has anyone else experienced this same issue? If so, how did you go about fixing it? I'm not opposed to completely disassembling the cube, but I'd like to at least have some idea what I'd be looking to accomplish by doing so.