SAMBA access to UCS Server shares terribly slow since 5.0-4 errata803

we noticed, that after upgrading to 5.0-4 errata803, the Windows 10 (Windows Updates 09-2023 NOT installed yet, only UCS upgrade performed) access to SAMBA shares has become terribly slow. In fact, it takes more than 30 seconds until the folder contents are displayed.
Accessing other SMB shares from Windows 2019 servers or NAS-shares are not affected.

Has someone a clue for me or which logs would be interesting to find the source of the problem?

Thanks and best regards,

Edit: sorry - I forgot: Windows Logs seem to be clean.