Well, it looks like I need a different device so...

What size base ring are you?

 

Steel holy trainer v4 and cobra devices seem to have a smaller diagonal ball gap

 

Are you sure about the hinged ring?
I cant wear devices with hinged rings without getting cuts and irritation.
When i started i bought a cheap stainless steel device with multiple size rings so i could vind the right size ring and by bending the right size gap.
Good luck!

 

Avoid anything with a hinged ring. It never fails to pinch and cut you. Look for a cage you like on amazon with a three ring set to get your ring size right.

 

I have that same cage and it really is heavy and starts pulling down then the extensive burning starts in. The hinged base ring has too much tolerance and even lock on has a lot of slack

 

I don't believe it's the gap that's the issue. Rather, it's the ring size. It needs to be tighter. Can't speak to the link you posted. Generally, I feel you get what you pay for. Before I got a new cage, I'd see if you can get a smaller ring for your soulock. They have a support email so I'd send them email and tell them it's falling off. They may send you smaller rings, or give you a discount.