To remove all metadata from files (audio, video, images ...), install the software:
sudo aptitude install exiftool mkvtoolnixThen type in the folder:
exiftool -r -overwrite_original -P -all= .
find . -type f -name '*.mkv' -print0 | while IFS= read -r -d '' i; do
echo "$i"
mkvpropedit "$i" -e info -s title=""
done