One thing you might want to look into is your computer’s sound settings, especially via the microphone. There are levels you can set withing Slobs, and even playback sound levels via each browser.
This is for Windows 10, microphone volume setting.
These are the different levels you can set via each web browser & application that is beyond what volume you set on a youtube page.
Your mic doesn’t have any gain control on the mic itself and depending on your actual room surroundings may just amplify your recording if you’re not directly in front of the microphone. Depending on how close you are to this mic can determine the record quality as well.
Best advice I can give you… don’t adjust any volume levels in Shotcut unless you have to. Run a few tests with OBS at various levels, upload videos to YT, but select “Private” for the privacy setting, then play them back. Make all of your adjustments before you record. It may take you 4 to 10 recordings to find the spot you want to be at.
If you really do want to adjust levels of your recordings every time you edit a video, then record your audio to a 3rd track. You can separate that mic track in Shotcut to raise/lower the mic volume without adjusting the entire video sound.
In OBS, allow 3 tracks for recording, Track 1: everything, Track 2: general audio, Track 3: Mic
How it looks in Shotcut
And every application/game has it’s own audio levels as well.
The right mix would be what you want. It took me several weeks to figure out where to have various levels where I want them to be at. For many videos I published I would always adjust the mic levels with Shotcut until I got tired of doing so.