Porta 02
Hey there,
I don't know how the switches are set up on this model, but make sure that when you record track 3 or 4, the other swtiches are turned to safe or off or whatever it says. From the looks at a porta 02, there are track 1-safe-2 and 3-safe-4. When you record track 1, make sure the other switches are on safe. The 2 inputs should be assigned to the track you are recording on. Keeping the other switches on safe, should prevent recording over something recorded. If that doesn't work, get rid of it.