When my home was brand new it too had that taste. Many months later it eventually went away. Taste/smell was blamed on the plastic line from the street to the house, 250 feet or so.
I myself would park along my woodline/ open the grey drains, and allow water to slowly flush thru the system. It will eventually go away.
2008 Jayco Eagle SuperLite 29.5
2014 F250 6.7 PSD 4X4, CC LB