I picked up my first Atmos Clock model 528-8 in what appears great condition. It is keeping prettying good time, running a tad slow. I have leveled it using the spirit bubble level. However, I have noticed that balance staff will wobble back and forth occasionally. It doesn't look like it is hitting the bridge during the rotational wobble. Is this wobble common? When I lock the balance wheel, it seems to bring it back to center over the bridge plate, indicating to me that either the clock is not level or the balance staff is bent somehow. I don't want to attempt to adjust the Fast-Slow adjustment until I determine if their might be another problem. The serial number is 220650 which I believe puts it manufacture date around 1966. Any comments relating to experience with this wobble would be greatly appreciated.