Specifically, the window to request the application comes up once, then VLC or GNOME MPlayer can't find /dev/dvd. Then this window fails to open on successive disk insertions. If I browse, I can find the disk title and play from that point. /dev was checked and confirmed /dev/dvd was absent. This is on installations on two machines Acer M3920 and Dell 1150. Confirmed libdvdcss2 and libdvdread4 installed.