Funny smell in finshed product

So I brewed a RIS from a recipe I found on HBT. It called for a whitelabs 002 I think but my LHBS only carries wyeast. THe substitue was 1968 esb? Witch I thought was strange but i went with it cuz the stout was a award winner. Long story short I didn't hit the abv i was looking for despite me doing everything i could and now there is a funny almost bad milk smell in the stout. I cant pin it down. Any help would be appreciated.

Yikes.

Kegged? in the bottle? What stage are you at? If primary or secondary, just don't smell it.

Yeah, we're going to need a lot more details here. Recipe, OG/FG, fermentation temp, mash temp, primary/secondary, etc.

Sorry, It's AG . OG 1.083 FG 1.018, Bottled for Three weeks now in bombers. Reciepe was here on HBT dont have it in hand i think it was 16lbs 2row and some other ****LOL.
mash temp was 155 for an hour or so ferm. temp was low 70's. I've never used this yeast before and it called for a long diacetyl rest so it sat in the primary for a month or so i then brewed a Southern english brown with the same strain and no problems. It taste great and old milk might not be the best way to describe it but there is something there i cant pin it down.

Well no info but the beer calmed down and now it tastes great