I've had the same smell off of fermenting that you guys are talking about. The only way that I fixed this was with really good and thorough cleaning and sanitizing. I wash my spoons, bottles, caps, hands, counters, siphon, measuring cups, and leave a little in the sink with a cloth / paper towel in case I need it again for anything.
I picked up this powered sanitizer from my LHBS ... it was white and doesnt require extensive rinsing (big plus).
I'd say you are very close just work out the cleaning / disinfecting and I think you've got it made.
PS: I used fleishmanns yeast and it turns out smelling / tasting funky as opposed to other champagne or wine yeasts.
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