Note: The DVD is addresses as 1 in that command. But if I run /usr/bin/mplayer dvd://0 from the command line, it opens and plays the DVD fine. So it seems for some reason running mplayer from smplayer assumes DVD 1 instead of dvd 0. BUT if I run /usr/bin/mplayer dvd://1, it ALSO opens and plays the DVD fine!
Can you please clarify something for me, before you go any further ? And my apologies in advance for this silly question - but I had to ask. In smplayer, one can specify under preferences, drive, exactly which dvd drive to use. If smplayer is setup wrong there, then it will go to the wrong DVD drive. Honestly - I can not tell if you went to that GUI location in smplayer.
Could it be a corrupted config file for smplayer ? I confirmed smplayer DOES play with /dev/sr0 and /dev/sr1 in openSUSE 42.3 LEAP on my PC, so this appears specific to something wrong specifically on your PC.
Try deleting .config/smplayer directory. Possibly do that after a deletion and re-install of smplayer. You also could try at same time deleting ./mplayer directory. The idea is to have a clean re-install of mplayer/smplayer with no corrupt config files. Its a long shot , but its good to remove mplayer/smplayer as the possible problem , before one starts to speculate on support apps.
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