Titling errors galore

I am having a serious problem trying to title my tracks- since the last iTunes 'upgrade' I find iTunes decides what the titles of my playlists and artists are! I am a producer with a specific naming system to the work I do and iTunes is arbitrarily disallowing me to title the tracks and artists as I want- in many cases it will use a capitalized misspelling of my own band no matter what I do or type or select. The only way I can add the correct info is to type it out in another app and copy/paste it and even then it sometimes will override even that!! Any help deeply appreciated.