After I could not play some DVD's, I have complained about the device and get a new one (not acquired amazon). With this device, the same symptom. Diverse Purchase DVDs are not recognized by the drive. On my second drive BH10LS38 these DVD's are detected immediately, however. Example "Kylie Minogue Body Language Live" no. 7243 599676 9 can not be played on BH16NS40.
Was my last drive of LG which I bought!
Those who want to watch DVD movies should be installed a second drive to be equipped.