Expert Pro 220/Melco issue

[DavidP]

David, have you considered moving the iMac temporarily so that you can try using it with a wired Ethernet connection to see whether that resolves the problems when you're streaming high-res files?  That might at least tell you whether a wired MacMini would be a worthwhile investment.

Regarding the lower volume of the USB connection: I don't know Audirvana at all so what I'm about to say might be nonsense, but by analogy with Roon I wonder whether there is a device-specific setting that controls how volume is managed?  In other words, perhaps the volume is controlled by something in Audirvana as well as the Devialet's own volume control?  If so it might be just a matter of finding the relevant setting in Audirvana to make it play everything at full volume for the USB-connected Devialet so that only the Devialet's volume control is determining the effective playback level.

Hi Ian, I might just do that. Moving the iMac temporarily would certainly let me know what's going on. 

The actual USB volume issue is not with Audirvana but with the Melco HD/Melco/USB/Devialet route. But I see your point about conflicting software volume control settings. (Interestingly, when I use my iPhone with mconnect if you switch to USB it resets the device volume to full on, switching to UPnP is resets the phone volume to where you were using it normally.) I think some more experimenting is called for.