Hi, welcome to librivox
All tech specs are correct and you're sounding great. However, the volume is a little too loud at 93.5dB. We aim for 86 - 92dB (with 89 being the goal). If you like you can install this tool which can tell you the dB of a recording.
https://cgjennings.ca/projects/checker/
You might want to turn down your recording volume a little. Also if you look under 'effects' you will see 'amplify'. This can be used to take volume down as well as up
Although there's not so much background noise that you
have to, you might like to consider running noise reduction to remove the background hum. Instructions for this can be found here
https://wiki.librivox.org/index.php/Noisecleaning_With_Pics
Once you've gotten the volume within the accepted range please upload the test again and post the link here
