There were (possibly still are) stereos that allowed the user to control the speed of playback from digital media as a function directed at karaoke users. These systems often also allowed pitch control independent from the speed.
As Mark says in his answer, the DAC (digital to analogue converter) in some stereos can run at slower or faster clock speeds due ...
Some software can upgrade the tempo without altering the pitch (increasing the tempo and the pitch is easier). Typically Reaper (with the Elastique technology), but I guess it is not the only software.
With such a software, you set the tempo coefficient, render it in a WAV or MP3 file and that’s it.
Decibels(dB) work in a logarithmic scale.
Every 10dB is perceived as twice as loud as the as the previous - thus 60dB is heard as twice the level of 50dB. (SPL doubles every 3dB)
This being the case, it can safely be said that 90dB will be perceived as twice the level of your 80dB background noise. The finer details will be up to you depending on how far ...
It seems the noise comes from the PC through the USB port and the audio interface doesn't filter it.
I would try an USB audio filter (like https://www.amazon.com/EZSync-Isolation-Filtering-ADUM3160-EZsync3102/dp/B01N4QX9XO), but I havn't tried it.
The M-Audio Fast-track outputs are unbalanced, then I doubt balanced cable will help (and I guess the output is ...