If you’re using the VOX mini player (not VOX Universal), open VOX’s settings and make sure Advanced > Output > Synchronize Sample Rate with player is checked. It’s possible that this setting is part of the VOX Premium subscription.
macOS likes to resample outgoing audio (there’s a whole thing with Apple Music going lossless hi-res and the OS just spitting out 16/44.1), but it usually outputs at 48hz, so getting 44.1 seems weird.
If the above suggestion doesn’t work, open Audio Midi Setup in apps/utilities, change the audio output settings to a higher sample rate / bit depth, and see what happens to your outputted audio. If it works, keep an eye on those settings when you restart, etc. as they may revert to 16/44.1. If this is the fix and it resets itself, you might want to try a free menu bar app called Lossless Switcher. LS listens to audio being sent through macOS’s audio engine and changes Audio Midi Setup automatically. It’s super handy for Apple Music.