The frequency only changes for the first new start, no problem there. Please try using the parameter „-o hw:1“ for sound output to circumvent any software problems. Please also try using shairport and other test files to rule out the files or player as a source of error. Finally, you might try giving the USB separate power supply with a powered USB-HUB. However, we have not had great experience with USB-DAC’s overall and recommend I2S native sound cards in general.