To change SAMBA version, via ssh type
  smb2status

  Code: Select all
  
  smbd (samba daemon) Version 3.6.25
  smbd (samba daemon) is running.
  max protocol SMB 1.0 enabled.



to change to 2.1 type
  smb21enable

or

  smb3enable



https://forum.qnap.com/viewtopic.php?t=134173