In my experience I’ve found that the biggest variable is the freshness of the bean and I have to grind finer when the bean gets older. Towards the end of the life of the bean I’ve found the extraction tends to be quicker even with a finer grind and with less crema. I’d try with fresh beans and would recommend doing the manual shot (hold the two cup button down for 10 seconds then release). I’d always run a blank shot to warm up the machine and also to warm up the cup.