Try this solution
Ensure that the amplifier is set correctly
Make sure you are using unbalanced cables (RCA/Phono)
Red tip should go in the amplifier socket marked as "right" and the white tip should go in the amplifier socket marked as "left".
Does your DacMagic 100 recognise the digital signal from your audio source?
One of the five horizontal LED indicators should be lit, indicating the digital sampling rate.
NOTE! For 32kHz no LED will be lit, but the DacMagic 100 will still operate.
Does the LED indicator display a light indicating which digital source is being used?
One of the four vertical LED indicators should be lit.