"Different audio systems use different rates of 44.1, 48, and 96 kHz.
Users would like to transfer source material between these systems.
Just replaying the existing data at the new rate will not normally work—it introduces large changes in pitch (for audio).
Hence sample rate conversion is required.
Two basic approaches are:
. Convert to analog, then re-sample at the new rate.
. Digital signal processing – compute the values of the new samples from the old samples." (i.e. resampling)
http://en.wikipedia.org/wiki/Sample_rate_conversion
The sampling rates of the Nook Color USB audio and your music are likely different; and the modded Nook Color USB audio has no automatic sample rate switching, no resampling, or its resampling is very low quality.
