Comment by nitrogen

You just need to consider more plausible explanations for the difference you are hearing, such as low-quality sample rate conversion on the playback devices you are using, clock jitter that is less audible at 192k than 44.1k, no dithering on the 16-bit output resulting in quantization noise on quiet sounds, etc.

If you're listening to quiet music in a quiet room at high volumes on very low noise equipment, you can hear a difference in the noise floor level between dithered 16-bit and 24-bit, but at that volume level if that music (or movie) also has full-amplitude signals you'll be reaching peaks over 110dB SPL.