How not? The speakers on the phone wont play the higher bitrate files, it will downsample to the standard 16bit/48Khz that android normally uses. However with headphones plugged in it can play up to 24bit/192Khz because of the upgraded DAC, AMP, and the rewritten audio stack (since android does not natively support sampling that high)
The only thing I don't like is that it can't output 24bit/192Khz over USB, it ONLY supports it through the headphone jack, not sure if it was a decision made by LG, or some sort of hardware limitation, or OS problems... :|