Omega DeVille 196.0256 Cal. 1430 movement help

The potentiometer on a quartz watch is usually good for single-digit seconds-per-day, since it counts on a quartz oscillator to get its time, and they are pretty darn accurate outside of manufacturing differences/temperature compensation.

Based on your video, there is a failed component, probably the divider, on the circuit board (since it is still 1 second jumps, but way too often!). There isn't really anything you can do about it unfortunately, other than replace parts. Fortunately whole movements arent' too bad (particularly if you're OK with the ETA movement that this is a re-label of).