I just received mine! uDac-2, black version, orderered from Hifi to Go in the Netherlands. Like I reported before I was afraid of the tone issue, but the store insured me that I would get a full refund if I experienced the tone.
Just plugged it in: at first with my Alessandro MS-1i. No tone! Nothing! No click when I turn the unit on, no hiss when I turn the volume all the way up, just nothing.
Then: MEElectronics M6: No tone! I hear a slight click when I turn the unit on, and a
little hiss when I turn the volume control way up. But that's all there is, I'm definately not hearing any of the tones posted earlier.
After that: Sony MDR-CD3000. No tone! No click when I turn the unit on, but a
little hiss when I turn the volume control way up. But that's all there is, I'm definately not hearing any of the tones posted earlier.
So, I am very happy with my unit. I cannot hear the tones that were posted earlier. If there is a tone, it would have to be one over 16 kHz, cause I cannot hear anything above that frequency.
Here is the questionnaire:
1. Can you hear the tone? ( if no, jump to question 9) >
no.
2. Is the tone louder than the background hiss? (a feel for how loud it is)
3. Does the tone change volume with the volume knob turning?
4. Estimate the frequency of the tone
5. Does the tone frequency change with different headphones?
6. Try different usb ports on the computer, does the tone change volume or frequency or is it identical on every port?
7. Does the tone occur anytime the udac2 is plugged in and on, whether it's playing anything or not?
8. Is there a tone if you plug it into a usb charger or hub without being connected to a computer?
9. List the computer(s) it is connected to and if any hub or extension cable is in between.
Sony Vaio FW11S laptop. It is connected with an 220V power cable (European) to the power grid, with a connector box in between. Running the laptop on battery does not change anything. Using Windows 7 Ultimate.
10. List the usb cable you are using it with.
Stock USB cable that came with uDac-2.
11. List the headphones you hear and don't hear it with.
See above (MS-1i, MEElec M6, Sony MDR-CD3000)
I'd be happy to answer any questions or do some more testing. Let me know.
(Oh and by the way, this is my first DAC and I must say I'm really impressed by the difference! Rediscovering my music
again! )