Layer issue

Hello, this is an issue that has happened several times since I started using Audacity a while ago. Thing is sometimes when I am recording different layers the sound from the previous layer is also re-recorded in the new layer that is being recorded. In normal circumstances every layer that I add should be only with the sound being sent to the mixer and therefore to Audacity. I’ve tried checking and unchecking several boxes within Audacity and Windows audio properties with no fix. As I mentioned earlier, it happens all of a sudden. I’m using Windows 7 both x86 and x64 versions. Any help would be appreciated, thanks.

The overdubbing process will supply the backing tracks to you during your fresh performance, you don’t have to “help it.”

Audacity > Edit > Preferences > Recording: [X] Overdubbing. Only. Don’t select anything else in that panel.

That in addition to explicitly recording your microphone or mixer, not a “fake driver” such as Stereo-Mix or What-U-Hear. Set this in the Audacity Device Toolbar.

This last business may be familiar to you as the settings needed to record internet music, YouTube playback or other on-line content. Those settings do not work with Overdubbing. They cross the music pathways by accident.