Removing Fabric Softener Odor from Down Comforter?

I always use very, very little soap and at least one vinegar rinse when doing my down comforters and usually do a second vinegar rinse just to be sure as this is not something that I do very often and mine always smell nice and fresh. One or two cups of vinegar is all that is needed for a full (large or extra large) load.

You may have to try doing a couple of rinses to remove this odor (and film) from your comforter.
I always begin my drying outside (sunshine) and when partially dry I then start drying in dryer with no heat to begin the fluffing (I use 2 or 3 tennis balls in my dryer) (adding a large dry towel helps this process). Check often to be sure it is not rolled into a ball. After maybe 25 - 30 minutes of fluffing, I remove the comforter and either return to out side or lay it flat over a sofa back to air dry a little more. Later, I return it to the dryer (no heat) to complete the task.
Goose down does not always do well with dryer heat and may even leave an odor of its own.
This may seem like a long (overdone) process but I have down comforters that are well over 15 years old and still look and smell like new.
Here are a couple of tips from comforter manufacturers about goose down:
Fabric Softener Not recommended because it will coat the down and reduces its fluff.
Clumping or Odor These are signs that your comforter is not dry yet. You want it to be completely dry to prevent mold.

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