My husband recently noticed a rash on his penis under the dome after we have a long sex session. He constantly worries about getting hard which is an issue but it takes him so long to ejaculate that I personally think that’s what is causing the rash. Like friction burn or something. We’ve been married 32 years and he’s 53. I don’t have a answer for him and he doesn’t know what to do. What else could be causing this??