Krisp virtual background is free for all Krisp users and has no time limitations.
If you don't see the Krisp camera in the apps you want to use it with, restart the communication app/browser. This is needed to make the Krisp camera appear in the available cameras' list.
One of the reasons that can lead to the problem, is when you use virtual backgrounds in two apps at the same time (ex: Krisp and Zoom backgrounds). The communication app background will treat the Krisp background as your usual environment and try to remove it, thus leading to a distorted image.
To avoid this problem, make sure to use one virtual background in the communication app when you use the Krisp one.
The virtual background feature is now in Beta. It can sometimes cause high CPU usage. That's because Krisp performs high video processing on your device. Currently, there is no way to lower the CPU usage when using the Krisp virtual background feature. We will however gradually improve it to apply less load on your computer.
The logic of the virtual background is to show one person - the main speaker. In some cases, though, other people that are close to the speaker may be shown through the background. There is no other solution than to stay alone in the focus of your camera.