In Elementary OS sometimes stortcuts (like Super + T) is not working. I have created this script as temporal resolve of this problem until it will be resolved by Elementary OS developers

fix_keyboard

#!/bin/bash

function send_notification() {
    notify-send -u low -i keyboard -c system "Shortcuts fixer" "$1"
}

function assert_success() {
    "${@}"
    local status=${?}
    if [ ${status} -ne 0 ]; then
        send_notification "### Error ${status} at: ${BASH_LINENO[*]} ###"
        exit ${status}
    fi
}

# id=`ps -u "$USER" | grep "gsd-media-keys" | grep -o "^[[:space:]]*[[:digit:]]*"`

assert_success killall -u "$USER" gsd-media-keys
# assert_success killall gsd-media-keys
sleep 5
assert_success /usr/lib/gnome-settings-daemon/gsd-media-keys &
send_notification Fixed