Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Funny Taste

I love the idea of this machine. I followed the instructions and ran thru a few cups of plain water to start, but there was a funny metallic taste to my cup of coffee. So I ran thru water and vinegar (per Keurig). Still funny metallic taste. Guess it has to go back. Too bad, because it would have been awesome!