Ok so recently my sourdough has stopped being sour.  I haven't changed anything!  Recently I started feeding my started twice a day and leaving it out on the counter.  It's doing as it should, doubling, bubbling, etc.  It smells sour.  I follow my recipe and the bread is not sour!  It rises, it doubles, it's fluffy etc but not sour anymore!  It used to get really sour.

 Now I bought my starter from King Arthur Flour, but I live in Texas... so I'm wondering if it's maybe that all the natural yeasts that I'm capturing are just not sour??? Or do I for some unknown reason need to try a different recipe?? 

I culture half the flour with starter and water for 16 hours before baking, 4 hours out, 12 hours in the fridge.  Then let it rise till almost doubled, shape it, let it rise, then bake it.  Bread quality is great, just not sour!