Comment 5 for bug 559628

Michael, alternatively, if you don't want ntpd to access /etc/ld.so.preload but want to silence the message, please add to /etc/apparmor.d/usr.sbin.ntpd:
  deny /etc/ld.so.preload r,

then perform:
$ sudo apparmor_parser -r /etc/apparmor.d/usr.sbin.ntpd