Eros Menegazzo

Hi everybody, I have a problem in my recording sessions: I have opened a new 4-tracks file, and recorded my acoustic guitar on track 1 and 2 (number one was a microphone, number 2 the acoustic guitar direct signal). Everytime I try to record some other instruments or vocal on track 3 and 4, Calewalk automatically re-record on these tracks the acoustic guitar that I have done on track 1 and 2. Does someone know why? Thanks, Eros