I'm currently typing this from an MX3200 too
Btw, that dynamic scroll/zoom function is kinda useless. That's why you have the arrow keys/page up/down
Also, my receiver has a problem: After some time of use, when I press a key that key is pressed many times. It only happens with that key. I remove and reinsert the receiver and it works fine then for some weeks.
There are some similar topics at logitech's forums.
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