vlc crashes when trying to play video files

Hello to all, novice Linux user here! Recently I upgraded to Ubuntu 16.04 and everything was running smoothly. Today (about 2 weeks after the upgrade) VLC stopped playing video files. Audio files play normally and other media players play video files without problems. To be more precise, when I double-click on a video file, VLC window appears momentarily and then closes abruptly without the video playing. Same result occurs if I open the video file through vlc menu. I removed and re-installed vlc with no effect. Trying various things on different forums, I found that I could make it work by entering 'vlc --avcodec-hw none --vout x11' using the terminal. It's the only way that vlc plays the files. I should also mention that I manually installed some packages in order to install acestream (which isn't supported on 16.04) and when that didn't work, I removed them. I think that the problems started after that.
Anyway a sample output from the terminal is:
VLC media player 2.2.2 Weatherwax (revision 2.2.2-0-g6259d80)
[0000000000f6d088] core libvlc: Running vlc with the default interface. Use 'cvlc' to use vlc without interface.
Gtk-Message: Failed to load module "topmenu-gtk-module"
[00007f6000c1bbf8] equalizer audio filter error: No preset selected
[000000000106b778] core audio output error: cannot add user audio filter "equalizer" (skipped)
Segmentation fault (core dumped)

Also for whatever it's worth, Kodi also doesn't play media files (problem started the same time as vlc).

Would greatly appreciate any advice...