Problem for a beginner

I am a beginner on audacity, having used it a lot to record in the past but I know only the basics.
I probably did a change in the settings and now every record starts from 0,5 level instead of 0.
I tried a lot to change it but nothing happened. I even removed audacity and download it again but the problem remains.
Please, can you tell me how to fix it? I hope the photo will help you to understand what I mean. Sorry if my question is silly but as I said I am a beginner!
:unamused: :unamused:

Thank you in advance…
audacity problem.png

You can get rid of it with Effect > Normalize: [X] Remove DC > OK.

But. That’s likely a broken soundcard. The soundcard is supposed to combine the battery or power from the computer with your voice in such a way that only the digitized voice is left. Your soundcard is allowing some of the battery to leak into the sound. You will never be able to reach full voice volume and there may be other distortions as well.

Describe your system. Which microphone? How do you have it connected to the computer?