/root is wrongly copied during update

[Albert Berger]

For backuping system folders on ArchLinux I use the following command
per folder:

rsync --update -DHAErlptgo --relative --delete-during $dir $backupdir

The problem is that every file in /root folder and its subfolders is
copied each time when this command is run. In all other folders only
new or modified files are copied. The files and the folder itself have
the following attributes:

[root at kw var]# getfattr /root/.bash_aliases 
[root at kw var]# getfattr /root
[root at kw var]# ls -ld /root
drwxr-x--- 29 root root 4096 Jun 18 13:51 /root
[root at kw var]# ls -l /root/.bash_aliases 
-rw-r--r-- 1 root root 113 May 17  2015 /root/.bash_aliases

On backup dir:

[root at kw var]# getfattr /mnt/backup/home/root/.bash_aliases 
[root at kw var]# getfattr /mnt/backup/home/root
[root at kw var]# ls -ld /mnt/backup/home/root
drwxr-x---+ 1 root root 0 Jun 18 10:02 /mnt/backup/home/root
[root at kw var]# ls -l /mnt/backup/home/root/.bash_aliases 
-rw-r--r--+ 1 root root 113 May 17  2015 /mnt/backup/home/root/.bash_aliases

Could someone advise what can cause such rsync's behaviour?

Thanks.

Albert.