It’s a click track if you produced tick sounds from the Generate tools, It can be a drum track if you live-recorded you or someone actually playing drums. A generic “backing track” is anything you’re playing into your headphones and performing to.
The goal of overdubbing is to produce a new, clean performance recording by itself.
There are a few different ways you can get stuck with multiple copies of the backing track.
– You can have Audacity set to intentionally include the backing track by accident. Audacity > Edit > Preferences > Recording > [_]Playthrough should not be selected.
– You almost have to be on wired headphones for an overdub performance. Speakers need not apply. Wireless headphones have interesting problems with sound routing, timing, and quality issues.
– You can have leaky headphones. Headphone sound can be so loud that it leaks out past your head and into the microphone. This is where “affordable” headphones are a problem. Big and sealed are good.
– You need to be recording from a real thing you can touch and feel. USB Audio CODEC is the name of my microphone interface. It’s a real thing I can reach over and touch. Stereo-Mix is a fake or virtual device designed to push sound pathways around for special effects. I can record from it, but I can’t reach over and touch it. Stereo-Mix and its sisters can create overdubbing damage.
– You can’t have any other sound software running in the background. No Zoom, Skype, or other communications or chat program. Turn them all off and restart the computer. If possible disconnect from the network.
– You can have more than one of those problems.
– You can have a playback problem as well. At the end of your overdub pass, you have to press SOLO on the left of your new track to hear your new performance by itself. Just Selecting your new track won’t do it. Selecting will play your new work and the backing track.
– A recent forum post points out that your performance can’t be virtual instruments. The computer settings to record virtual instruments and settings for overdubbing are incompatible.