In Cinnamon the volume will only go to 100% using the keyboard volume keys, but will go to 153% using the GUI slider. To use the keyboard keys to go to max volume you will need to change the volume keys to a different command.
To start go to Preferences > System Settings > Keyboard > Shortcuts then Custom Shortcuts.
Then Add Custom Shortcut for Volume Down and Volume Up. In the Command line enter “pactl set-sink-volume 0 -10%” for Down and +10% for Up. Then assign the keyboard keys.
If the volume still will not increase above 100% you will have to delete the default assigned keys for Volume Up.