Capture Schedule delayed and stops after few days

I have few DS-2CD2512F-I set to capture a snapshot once a day. The Picture Capture/Capture Schedule is set to 12-13hr and the interval set to 1 hour (3600000 ms). It capture an image exactly 12:00:00 and saves it to the FTP server. This scenario works flawlessly for many years. Now I've bought a new DS-2CD2543G2-IWS, FW V5.7.23 build 260320. This model does it wrong. The settings are 100 % the same, but the snapshot is delayed by several minutes. The delays are following:

three days are capture on 12:05:51
next days are like 12:18:09
etc.

After few days it stops saving the snapshots at all! So I have to recheck and re-save the settings to make it saving again (still time-shifted). It saves about 3 days and then stops again. Why? Older cameras work fine same settings, same ftp server, same ftp account.

Sure, all cameras are NTP synced and show correct time in live view. I suspect that the scheduled capture does not work when a motion detection is being detected at the same time. At the time i type this message, the camera saved the image correctly at 12:00:01 and there was motion detection invoked recording on the NVR server. While other days, when the image capture was delayed, there was a motion detection recording running in the background. Maybe the motion detected recording has higher priority and the scheduled image capture is invoked after motion stopps. However the other models mention in my first post have no problem capturing image on time while motion detected recording runs in background.

Unfortunately the NVR cannot run scripts, however I've made myself a program for live viewing the cameras with the possibility to capture image or video on a button click. This works with no problem, even when the camera is registering motion and is reporting the motion to the master NVR, I can click my save image button at any time and get the desired capture at the right time. I think there is a problem with the priority of events settings inside the camera. The picture capture has apparently lower priority then motion trigger. And this should be viseversa - capture scheduled image and then checks for motion. However I've set the time span schedule from noon until 2pm with the interval 1x a day. In my opinion this should capture the image at 12:00 if there's no motion at that time being detected. When the motion is being detected, the scheduled capture will be delayed until the motions stops. The schedule capture will "wait for camera to be ready to capture" until 2 pm. That is what I think it works.

Confirmed. I had motion detected alert and NVR being recording during noon and no scheduled picture capture was saved. I extended the scheduled window until 2 pm. At that time there was no motion and the picture was saved immediately.
Conclusion:
No scheduled picture is taken at the scheduled time when the motion detected is reported at the same time.