No option for "always record new track" on preferences menu

I am running the latest(?) 2.1.2 Audacity on Ubuntu 17.10. I got it through the Software Center; at the click of a mouse “install”

When I go to “edit” “preferences” “recording” there is no menu choice for “always record on new track” or “detect dropouts,” for that a matter
(everything under “sound activation level” is not there…compared to screen shots I’ve seen of other recording preference menus…
I do want a second track but only want to overdub over a few seconds of selected region in the first track.

I have to manually “add new mono track” then put the cursor somewhere before the selected region then shift+R and it will move, I will hear the first track being monitored, but it won’t record until the cursor is moving under the highlighted area then will continue to playback but won’t record past the highlighted section.
If I just click record it will make a new track and then do nothing.
A second click opens yet another new track which just sits there.

But, I’m missing “always a new track” on the menu, and wonder if that is part of the other problem…
Sorry I have no screenshots or core dumps (LOL) for you

That may be the latest version in the Ubuntu Software Center, but the latest release of Audacity is 2.2.2.
The on-line manual is for the current (2.2.2) release version, so you will notice some differences between the on-line manual and the version of Audacity that you have.
The 2.1.2 manual may be downloaded from here: Audacity download latest version
Installation instructions for the manual are here: Unzipping the Manual - Audacity Manual

In Audacity 2.1.2, recording to a new track is the standard behaviour. There is no option to change it (added in 2.2.0 I think).
If you want to record to the end of an existing track (in 2.1.2), you need to “append record” (shortcut: Shift + R)

The “detect dropouts” option is a new feature in Audacity 2.2.2.

That would indicate that there is no active audio stream.
What are you trying to record?
Are you using a standard Ubuntu installation with the standard (PulseAudio) sound system?