Grinder whines, too many fines [DF64V v3]
I bought a new DF64V gen 3 in March, and finally got delivery in lateJune, about a month ago. I do lever-pull (robot and flair classic) espresso drinks as well as pour overs. I'm not an expert in either, more of an advanced beginner. Previously, used manual or electric rotary burr grinders. I wanted more convenience, precision, and ability to play with flavors.
Since arrival, there have been issues. I need help figuring them out. The machine is nearly silent when empty, but since the first use it has had a high-pitched whine after every grind. This happens every time, even if I feed just one bean. RPM setting and fineness don't matter. It goes away if I change the grind setting to coarser while it is on but empty, and gets worse if grind setting is made finer. For example, if I grind at 35, it goes away at 36, but comes back at 35 and gets worse as I go lower. I have taken the burrs apart and cleaned them, and confirmed that it is caused by retained grounds. I checked zero point. I have not checked alignment yet. I am guessing I have an alignment or electronics issue, but would appreciate advice. I can work around this, but is it normal?
Also, at the end of every grind, the rpm speeds up, I believe to maximum rpm (1800). It lasts a couple of seconds and goes back to the set rpm. However, it seems that the high-rpm grinding is finer, or has more fines, than the rest of the grind. It only affects a retained bean or two. This causes problems with grind consistency. Is this normal behavior, or is it trying to clean the retained beans? Or some other issue?
It has also stalled several times. I always do a hot start, and usually grind espresso at 1000 rpm, pour over at 800 rpm. Medium beans for espresso, and light to medium for pour over. No extreme light roast. It even happened on pour-over coarseness, around 75 setting. Again, is this related to the retained beans? The stops were sudden, without any indication of motor strain. I did get an error code. I don't slow feed, but there is some sort of slow feed/anti-popcorn device built in.
There are more fines than I expect, or size inconsistency.. Draw down for pour over is extremely slow, even with coarse settings like 80, it can take 6-8 minutes. And espresso requires a setting in the mid-30s with medium-roast beans. The excessive fines is my biggest issue. It really interferes with pour over.
I have been told by customer service that this is normal behavior for a flat burr grinder, and that it should go away after break in. Is this normal behavior for a new machine? What can I do to reduce fines?