Stinky Septum Piercing?

So I've had my septum for about two years. Never really had any issues. Occasionally I get that dreaded cheese smell, which a quick wash will clear right up.

I did recently stretch from 14 to 12, about 2 months ago. The first jewelry I used was a rainbow steel pincher and it was fine. Now I've switched to a plain stainless steel ring and the smell is just awful! Like... rotten milk or something. I wash my face once or twice a day and get in there and wash the piercing and jewelry. Occasionally throughout the day, when washing my hands, I'll swirl my wet fingers around in my nose as well.

Im wondering if it's the specific jewelry but I've never had issues with stainless steel. I'm wondering if anyone here has had issues with uberstink in their piercings and if specific metals made it better or worse?