My Mauthe (made approx 1925) box clock which for the last five years or so has been keeping time to within about 30 seconds per week and which is wound on Sunday mornings and Wednesday evenings, is losing time. For the previous 2 Sundays I have not had to adjust her, as she was bang on when I checked the time as per the world clock on my PC. On the Sunday just past, she was about 3 minutes slow. I corrected her after winding and now, on Wed evening she is about 1 minute slow. She has not been moved and has Bostik Prestik securing her to the wall to prevent accidental moving while being wound. She is probably due for a service and I would have thought she would begin gaining, but she is losing!!! Any ideas as to what could be causing this?
Most visitors online was 1660 , on 12 Dec 2020