DIAGNOSIS The taste is from manufacturing residues or carbon dust inside the new filters and chambers. It is not harmful but must be flushed.
FIX Step 1: Perform a full priming sequence for the filters, even if done previously. Step 2: Assemble the system. Step 3: Fill the upper chamber completely and let it filter through. Step 4: Discard this first full batch of filtered water. Step 5: Refill the upper chamber a second time. The taste from this batch will be normal.
IF THAT DIDN'T WORK Wash all chambers (upper, lower, lid) thoroughly with mild soap and warm water, then rinse completely before reassembly.
HEADS UP The initial flushing process is mandatory. Consuming water from the first cycle without discarding it will have the off-taste.