Plz some sex advice

I am in need of some help n advice. So my partner n I have unprotected/protected sex, depending on our moods. I am also on birth control too. Anyways, my partner has recently found almost like a rash under his foreskin. We don’t see other people by the way. He said that his dick is very sensitive n that in the summertime it irritates a lot more. He also said it could be my ph balance causing that to him. Does this sounds right? Like is that even a thing?