Ok. A friend of mine has an older Tag Heuer 2000 Professional (1989 quartz ETA) that was gaining time after a battery replacement. He shipped it to me to take a look and it kept perfect time on my desk. (???) Skeptical, I wore it for a day and noticed it was running at about twice the rate. Shock? Dirty? Took it off and set it on my desk again and after several minutes, it went back to keeping time. Can an increase in temperature cause the problem? Evidently. I hung it over my desk light (LED) which is slightly warm like an arm. Sure enough, started racing again. I did a quick circuit swap and now works perfect. This is a first for me. Has anyone else seen this??