problem solved!
after countless tests and recabling (now, this is a good thing with the lockdown!)
there were 2 issues :
(1)
SUB needs to be fed from the same power source as the DEV to avoid ground loop buzzing,
(2)
with the SUB I also replaced my mac.mini external drive to a 2TB SSD, without paying much attention to the USB port connections, so that:
- the SSD ended up on the USB1 port (my mac.mini 2012 has 2 of those!), and
- the DEV-DAC ended up on the port that is shared with the Bluetooth controller.
Changing these to the 2 exclusive USB2 ports fixed the sound quality issue!
P.S.
now the problem is that
- I need to use a very long power cable to connect the SUB and,
- the SUB's Auto power mode doesn't seem to work, and needs to be ON all the time (not sure this ever worked)
after countless tests and recabling (now, this is a good thing with the lockdown!)
there were 2 issues :
(1)
SUB needs to be fed from the same power source as the DEV to avoid ground loop buzzing,
(2)
with the SUB I also replaced my mac.mini external drive to a 2TB SSD, without paying much attention to the USB port connections, so that:
- the SSD ended up on the USB1 port (my mac.mini 2012 has 2 of those!), and
- the DEV-DAC ended up on the port that is shared with the Bluetooth controller.
Changing these to the 2 exclusive USB2 ports fixed the sound quality issue!
P.S.
now the problem is that
- I need to use a very long power cable to connect the SUB and,
- the SUB's Auto power mode doesn't seem to work, and needs to be ON all the time (not sure this ever worked)
Mac Mini + Matrix X-SPDIF2 + Echoes Music 1 | Pro-Ject CD Box RS2T ⏵ Devialet Expert 250 Pro ⏵ Boenicke W5 SE, B&W ASW 608 Sub
