Yeah I had a blade grinder for a while, the blades get dull and then you get inconsistent grinds. You could try just running some warm vinegar and descaling the machine but making coffee is a process that works best when you can eliminate variables. I went through 2 deLonghi's and two grinders before I switched to a Flair 58 and a Breville Burr grinder. Also, if you don't weigh your beans for dosing, you could just have too many grams of coffee in the portafilter. Too much volume with clog up the portafilter.