Mature Metal discussion

I’m still struggling with my JailBird and would appreciate any advice. My plan was to stay locked for whatever duration My Lady decides—anywhere from days to weeks. She doesn’t want it longer, nor do I. Two issues have forced me to request early release: The first is a “burning” feeling at the bottom of my scrotum. Lube helps somewhat, but after one painful escape despite using lube, I’ve become careful with it. Moving the skin a little can relieve the sensation for a while. This brings up the concept of “mind the gap.” Some people say a narrow gap causes this issue, yet others argue that if your testicles are high and tight—which mine are during daylight hours (I have no trouble at night)—a smaller gap is actually preferable. These views seem to clash. The way I measure the gap confuses me slightly: measuring between the closest points of the cage and ring gives 1/2”, but along the locking pin it reads 3/8” . My order confirms a specified gap of 3/8” which appears on the acknowledgment too. Another occasional issue involves two muscles or ligaments (?) connecting the base of my penis to my body becoming quite tender, even though I wear supportive underwear. This feels like a mix of weight and restriction, but there might be other causes. Given postage costs and usual shipping delays from UK to US, I hesitate to return it to MM unless I know exactly what needs fixing, assuming adjustment will help. The cage fits well, and the ring size is comfortable aside from these issues. Perhaps it’s just my anatomy! I’ve thought about using ball-stretchers to loosen things up—this seems relevant because when I’m relaxed in bed or warm, there’s no burning, but during work hours it becomes a distracting nuisance. I should note that lock-ups vary between two weeks and two days long, averaging once per month.