The barista at my local shop said my grinder was the problem, not my machine, and I owe her an apology
I have been fighting sour espresso for about 4 months, messing with my machine's temp and pressure, buying new baskets, the whole thing. The barista at the shop on 5th, Maya, watched me complain one morning and just said "your grinder is the weak link, I promise." I brushed it off because my grinder cost $180 and I figured that was plenty, but I finally borrowed a friend's nicer one for a weekend and the shots came out sweet on the first try. Now I feel dumb for all those nights I spent blaming my machine and burning through 3 bags of beans. Anyone else had someone call out the real problem when you were sure you already knew the answer?