I've noticed a chemically, astringent kind of off flavor in most of my beers, especially noticeable in my pale ale and other lighter beers (but it is present in the darker beers as well). At first I thought it was the dreaded "extract twang", but I went all grain last year and its still there. Its a harsh, very bitter astringency that is strong in the aroma and in the taste. Others don't notice it as much as I do, but that's typical I guess - I am my harshest critic.
Some research has led to the idea that it could be caused by chlorine or pH levels of my water. I use City of Milwaukee tap water, which I've always heard is fine "as-is" for homebrewing. The city indicates that Chlorine has a median level of 1.10 mg/L and pH is 7.68. I can post other parameters if helpful. Thanks for thoughts as to things I could try to identify and fix this issue.