ACL X-Flags removed on new files

Hi,

we have TrueNAS-13.0-U6.1 running and without changing anything we got problems with ACLs recently:
Every time we copy an executable file from Windows (Linux as well) to an SMB share, the executable X-Flag is removed. Despite of that, TrueNas claims the ACL has been inherited.

These are the ACL of the pool “install”:

root@store[/mnt/data]# getfacl install 
# file: install
# owner: root
# group: domainadmins
group:installateure:rwx---a-R-c---:fd-----:allow
            owner@:rwxpDdaARWcCos:fd-----:allow
            group@:rwxpDdaARWcCos:fd-----:allow
         everyone@:--------------:fd-----:allow

When a file is copied to that pool (smb share) the ACL of that file looks like this:

# file: install/ChromeSetup.exe
# owner: admin
# group: domainadmins
group:installateure:rw----a-R-c---:------I:allow
            owner@:rw-p--aARWcCos:-------:allow
            group@:r-----a-R-c--s:-------:allow
         everyone@:r-----a-R-c--s:-------:allow

As you can see, even in the default ACL entry of owner@ the X-Flag got removed.

When a file is copied via scp the ACLs are beeing set correctly:

# file: install/ChromeSetup.exe
# owner: root
# group: domainadmins
group:installateure:rwx---a-R-c---:------I:allow
            owner@:rwxpDdaARWcCos:------I:allow
            group@:rwxpDdaARWcCos:------I:allow
         everyone@:--------------:------I:allow

We run out of ideas as this setup ran flawlessly for ages. Hints and idear are welcome an appreciated.

Best
Simon