So since I have the Qutest I had a problem with powering it. The stock psu is a EMI/RFI generating monster, like all swithing power supplies. Noise was coming through my PC, monitors, amp and even headphone wires. No idea if this extra noise has any effect on sound or not, but for me it was annoying. Powering directly from PC's usb port everything was silent. Didn't have this issue with DAVE, everything was silent. I see some had some complaints on the TT2 forum aswell with feeling tingling by touching the case.
I got an Ifi iPower 5v to see if its better then the stock psu, but it had the same noise. I even considered buying a hifi pci e card to power Qutest, since this issue bothered me so much.
Even the power bank battery had EMI/RFI injected into Qutest. Until, by random testing, I introduced the battery with charing usb to PC's port, and behold, all the noise was gone. I guess it all went to the ground. That got me thinking that if I can somehow ground Qutest all the noise will go away.
And I've found the solution, it's called iFi Audio- Groundhog. Connected to the Ifi iPower 5v all the EMI/RFI is gone. Everything is silent as it was with DAVE. Don't know if this will work with stock PSU, needs an adapter, or if this will also work with TT2.
Such a cheap solution to a problem that I don't know if it affects sound quality or not, but for me it was bothersome. Will attach a picture to see how its connected, Ifi iPower 5v comes with an adapter DC jack to micro, the groundhog is between DC in and the adapter.