When you're not wearing the watch, try experimenting with setting the case in different positions (e.g. dial up, dial down, crown left, right, etc). Some positions will cause your watch to run faster, slower, or dead on due to gravity, side load and so on. If you have your COSC certificate, it should list which positions your specific watch generates +/- as I believe they time the watch in the different positions over the course of their evaluation.