I've been brewing and making wine for about 7 years. Beers are great, white wines are good but, I've never made a good red wine. My reds, mostly from high end kits from various mfg, all exhibit the same metallic taste at some level. They all are clear and bright with good color and have no identifying issues I've been able to discover. The whites have never exhibited this issue. This characteristic flaw does diminish with time but it never goes away totally. Any thoughts on what would cause this metallic taste unique to red kits? My reds made from fresh grapes do not have this trait.