E.R.
I had the same problem! If you have any glasses with current residue clean/rinse them with vinegar. If it comes off you have hard water. I just put vinegar in the liquid deparment for liquid residue cleaner and it works like a charm!! Hope it works for you too! (I still also put a basket of jet dry in my washer too - but the vinegar is what's working - I know because I tried all the residue products out there!!)