Mine is showing a lot of zero. I went for a 20 mile ride last night, and the computer recorded 9 of them. I'm not sure how much of today's ride I "got credit" for, but I looked down a few times and saw zeros. The speed and cadence seem to come and go at the same time. The magnets seem to be aligned properly.

Battery? Time to smash the computer and look for a new one? I got this one about two months ago, with the bike.