\\ in tag fields

How do you remove \\ from your artist and title field

You first should check if you have Multiple Artist and or Title Fields through
Extended Tags or ALT + T. (multiple-valued fields are separated by \\).

If not, why not create a Replace Action
http://help.mp3tag.de/options_format.html#replace

And if you want to combine Multiple fields into only 1, then
(Example uses the field ARTIST)
Create an Action Format value
Field: Artist
Format String: $meta(artist)

Update 13:22, Added Screen shot