L-Adapter

The noise seems like when you phone and it's busy this kind of noise is only playing music, without music hiss like white noise.

Both kind of noises it's only in right channel like with the SMPS.

When upsampling to DSD it's more strong so surely laptop polluting the sound.
 
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Maybe the laptop prefers floating because its normally a battery operated device. When on SMPS recharging mode we don't know if the DC output is referred to mains either. In general try NTC thermistor for mains earth to chassis and/or the L-A's DC out zero should be tied to its chassis.