@HOzosch Greetings! He's the person behind the 22 kHZ upsampling in Eloquence 64-bit. So feel free to address him here re upsampling and audio quality. And, BTW, V18 of Eloquence 64-bit with 22 kHZ, based on @fastfinge 's awesome efforts is also available now:
github.com/hozosch/eloquence_64/releases/download/v18+upsampling/Eloquence-v18+upsampling.nvda-addon