Rocky Doser Owners

[Blueface]

Or anyone that knows about them.

I have now had two or three experiences where although there is ample beans in the container, the grinder does not seem to grind at all.

I have tried moving the beans around with my hand and ultimately had to shake the heck out of the grinder while it was still on and grinding.

Anyone experience this?
Should I be concerned about a warranty problem or is this normal for the wear?