Can CO2 introduce bad flavors?

I got my Ninja Thirsti today and I tried it with 5 flavors now and I hate to say it but all 5 seemed kinda off to me. Since diet soda flavors are a very YMMV (your mileage may vary) type of thing I was already expecting to dislike maybe one or two or three of them, but damn, all of them have this poor artificial taste.....it has me wondering. Have people ever experienced better flavor overall when you switch up your CO2 source?