I use Mac Book pro (2016) and set playback to DSD64,128 & 252 and have the following result:
DSD64 up to DSD128 - Volume Control Mode: Use Device Control; DAC shows 5,64 MHz = play = OK
DSD64 : DSP Volume; DAC =352 kHz = hiss + music play
DSD64 : Fixed Volume; DAC 5,64 MHz = OK
DSD128 : UDC ; DAC 5,64 MHz = OK
DSD128 : DSP-V; DAC 352 kHz = hiss + music
DSD128 : FV ; DAC 5,64 MHz = OK
DSD252 : UDC ] DAC 5,64 MHz = OK
DSD252 : DSP V; DAC 352 kHz = OK
DSD252 : FV ; DAC 5,64 MHz = OK
So if setting DSP Volume, DAC shows 352 kHz and DSD64 & 128 have hiss, DSD252 has no hiss and play normal.
Any explaination? Which VCM is best to use?