Static noise help please


Recently just notice Static, hiss, popping sound(I don’t think I hear that before but I might be wrong) from both speakers when volume alway down with music off. Happen only when connected usb from iMac to Schitt Modi 2 Uber DAC. Static noise disappear after unplug either end of the usb. I am using temporally cheap 15 feet usb a/b cable. Pre amp is ARC LS7,ARC VS60 amp,and Sonus Faber Venere 2.5.  Any advise?
I swap from ARC setup above to Cary SLI80 interested amp and used the same usb cable and the static noise was gone. So I think it is not the usb cable problem. Is that possible static noise come from tubes?

Regards,
Eddy

eddy1
Hello ghosthouse,  This guy on Computer Audiophile had similar problem and use something similar to Audioquest Jitterbug and solved his problem.  Here is the link, the last posted shown what he used,  http://www.computeraudiophile.com/f6-dac-digital-analog-conversion/noisy-schiit-modi-help-needed-oth...
What do you think about Audioquest Jitterbug and the one that he used here
 https://electronics-shop.dk/galvanically_usb_isolation.htm?currency=EUR

The guy at Schiit told me to try certified USB 2.0 under 2 meters.  And I don't think this is the problem because I did with 4 feet USB and still got static but will go out and buy certified one to try out today if I can find one, mostly have to order online.   
"The Gungnir does not have a USB input." ghosthouse, I'm listening to my Gungnir Multibit via USB right now as I type. It certainly has USB input. 

Eddy, agree to try a certified USB cable. If ordering online check out Blue Jean cables on amazon or their own website, very affordable and reliable source for ethernet, usb etc. 

The galvanic isolator would probably help, but for your temporary setup, not worth investment. Wires are all antennae. Experiment with physical layout of the computer, dac, etc. Minimize wires touching each other and when they have to cross, try to keep at right angles. Bundle extra length with plastic ties or twisties from grocery store(not as good because there is metal inside). Neat cables minimize noise. Cheers,
Spencer


Thank you Spencer for your advised.  Been driving around to find Certified USB but no luck.  So I ordered Blue Jean USB online and the price is real good.  I guess I have to wait for a week to find out.
Spencer - Wasn't trying to generalize about all Gungnirs - but can see how what I wrote could be understood that way.  Had I written "The Gungnir in MY system does not have a USB input.", things would definitely have been clearer.   Good clarification.  

Eddie - I can't compare that galvanic isolator to the JitterBug.  Sorry.  The JitterBug is only $50 or so from MusicDirect and they do have a (60 day?) return policy, so you could try it and send it back if it did not fix your problem.  

Schiit also makes something called the "Wyrd USB Decrapifier".  $110 from Amazon.  See link here:

http://www.amazon.com/Schiit-SCH-16-Wyrd-USB-Decrapifier/dp/B00LFVMC9U

I take it you have tried other USB ports on your MAC as well as moving the Modi from near the monitor, etc. (as suggested on that Computer Audiophile thread).









ghosthouse, Yes, I tried all USB ports on my Mac and the Modi is far away from the monitor but still got static.  Will see if the certified USB would help but I don't think it would, well I will have to try.  Will report back when I the new USB come in.
Thank you,
Eddy