One-hour divergence in Google Calendar appointments

Good evening,

I have a rather strange problem. When I publish my (CalDav) calendar to Google, all appointments that were created in emClient are off by one hour. This problem does not appear when I create appointments on other devices (e. g. my iPhone or directly in the CalDav online interface) or when I publish the calendar to Outlook Online.

Does anyone else have this problem or knows about a solution? Thank you!

Alex