Metallic taste? I've read somewhere what can cause that... Of course I can't remember. If it's a kit, I would at least shoot the maker an email to let them know. If it goes away good, but it's better to give them a heads up so if in six months you try a bottle and it's still there then you have to chuck it. Then maybe they'll be more likely to believe that you aren't trying to get a free kit from them.
I did find this on Jack Kellers site:
Metallic Flavor</font>: Rarely, the use of
canned (tinned) fruit or berries or even juices can result in a
metallic taste to the wine made from such ingredients. This occurs when
a highly acidic ingredient sits too long in an poorly tinned can and
absorbs flavors from acid-metal interaction. This is not a common
occurance, but the taste does spoil the wine. Nothing can be done to
correct this off-taste, but you can avoid the offending brand in the
future.
Or
Most wines will clarify on their own given enough time and
appropriate rackings, but occasionally one won't. The problem could be
a pectin or starch haze, or perhaps a metallic contamination from using
copper, zinc, iron, or aluminum utensils.
I've read something else that can add metallic flavor but can't recall from where. Maybe from WineMaker magazine. Maybe someone else will recall for us.