This is something that has plagued the SP3 as well. Periodically when I wake my machine up from a sleep the type cover does not respond to any input from the keys or the trackpad. I've always had to detach and reattach the type cover. I might just upgrade my type cover and pen. After trying the pen on the SP4 the extra friction it provides on the glass surface is superb. I already thought the Pen on the SP3 originally was good.