Breville Barista Express

I’ve found that to get the proper extraction time, I need to adjust the burr setting inside the grinder. The problem is it’s always full of grounds and it’s difficult to get them out. Does anyone have any suggestions? I’m using 17 grams of Pete’s coffee with filtered water. It likes 25 seconds. Anything more and it tastes burnt. Up one on the dial (coarser) it’s too fast. One finer goes too long.

Also, I feel like this machine is really fussy. Even the same beans (but a different bag) will have to be re-calibrated. I’ve also found that if let my machine heat longer than 20 minutes, the extraction time changes. Has anyone experienced this? I would happily pay to have a class on dialing in beans on this machine. I’ll admit I’m a new brewer but I’ve had this machine for over a year and sometimes I still struggle.