Newbie question re: input routing

I’m a new user of Cubase 10 Pro (and have considerable experience with Pro Tools and Digital Performer).

I’m setting up a test project with VST Connect SE.

I selected channel 3 of my audio interface for the Talkback mic.

My question is: why am I seeing signal from the mic in the “Stereo In” mixer channel, as shown in the attached screen grab?

What is the purpose of that channel and how did it get created?

I’ve tried looking a few places in the Manual without success.

Thanks!

Press F4, go to your inputs section. If I understand your situation correctly you have a stereo input active. You can delete that and make other inputs as you desire.

When it comes to VST Connect, the free version, it only records stereo and it’s quite so annoying if you just want record 1 mono channel