While grinding during my last use, I noticed that my hopper was getting low on beans. The Compak K10 Fresh seems to be very sensitive to the bean weight in the hopper as it produced an excess amount of ground espresso in the timed grind, a lot more than usual.

This morning before making Espresso I added about 6oz to it. Just after the start of grinding, however, it made an usual change in noise pitch while grinding. It seemed to start at a lower pitch and go up in pitch a second or so into the start of grinding. A more 'normal' amount of espresso came out in the timed grind, but my shots came out way too fast. I did not adjust the grinder settings, and the beans I am using are the same as I had in the hopper before. They were frozen and vacuum packed, and I removed them from the freezer this morning and let them thaw on the counter before adding them to the hopper, a normal procedure for me.

Has anyone else experienced this noise change and have an explanation for why it happens? Could it be the density of the beans or possible an air pocket between the old beans in the chute and the new beans? Also, do you think there is a correlation between the grinding and the fact that the shots I pulled this morning were way too fast? After I shut down the pull, coffee still was dripping out the PF for a few seconds, which does not normally happen, so it even further makes me think there was something about the grind which was not good/normal.

Thanks.

I'm not sure about the change in pitch but I wouldn't worry much about the fast running shot. We all know that retention on doserless grinders is quite a bit and you're probably noticing the remnants from when the bean column ran out the day prior.