I think I found out the "error". The reset takes place when I (server) synchronize my tablet (Android) to the iOS tablets (clients). In fact, personal settings shouldn't be changed? Or? I have attached a photo of the synchronization settings. The same happens, when I synchronize from Android to Android. ... I find out that the META- setting also change the duration... I thought, that the duration settings are personally settings.
Armin
Armin