Now I realize what was the question!
III) 'sentirti' in /Non vedo l'ora di sentirti/
is always /to hear from you/, unless two intimate persons want to make a kind of joke, where /sentirti/ would have the meaning of /toccarti/ (to touch), and even in this case reception of the (unusual) meaning is guaranteed also if other non verbal hints are there (tone of voice, common reminescences, proximity, etc.).