Tascam us 32 how to disable "direct monitor"?

[Kriss Laven]

Good day. I am from Russia, I am writing via GOOGLE translator, so I apologize in advance. Recently, I bought an external sound card TASCAM US 32. Having connected it, I ran into such a problem, I can’t figure out how to disable "DIRECT MONITOR" in The official program found this item, but it is "gray" not active, I can not press the button to turn it off. I hear my voice, and when recording vocals, the sounds of tracks with music are superimposed on the vocal recording. What can be done? I rummaged through the entire Internet, I can not find anything, I use the MAC OS X Mojave system.