I have an all grain pale ale in the corny, and it smells and tastes like sulfur. 10 days in the primary, 14 days in secondary, and now 10 days in the keg. I put it in the refrigerator for the weekend, and when I attached the CO2 line and turned the pressure up, it was hissing around the seal (first time my seal has dried out!). When it went into the keg it was fine (no sulfur). I resealed the corny, and there it sits.
I have searched, and it seems that most sulfur smells happen in the primary with hefes, or lagers but I use safale us-05 consistently and haven't noticed this before. One possibility is that I primed the keg with corn sugar, instead of force carbing. (I usually use dme to prime).
I'm leaving the keg alone for now, but any hints or ideas are appreciated.