Help <3
I just got this thing and it’s stacked quite gorgeously beside my THX 789 ready for some A/B comparisons and all I hear when I have the A90 in is a slight bit of static at any point when I turn the volume past 12 oclock.
RCA plugged into GRACE SCAD. I’ve tried a couple different surge protectors.
What could be the issue?
So is it only static when you turn the volume or is it static all the time after the point on the volume knob? Also is the static more a hiss/white noise or clicks and pops? And also using the same dac you don’t have this issue with the 789 correct?
Thanks for your quick response.
It’s volume at any volume past 12 oclock. I hear it really bad when I move my mouse around.
Hiss/white noise for sure.
Same dac, 789 no noise.
It’s a ground loop then, try unplugging the dac and seeing if the noise issue still persists to test
Thank you! I keep hearing terms like “grounding issues” or “ground loop”. can you explain this to me like I’m 5 before I google too deep 
Without getting technical, it’s when you have multiple devices with different electrical grounds electrically connected together I think lol. So just wondering, are you splitting the rca coming out of the sdac to both the thx and the a90?
Okay. Ill try different USB slots.
And no splitting. the SDAC only has the 1 output and I was just switching the cables from THX to Topping
Gotcha. So is the a90 connected to the same or different outlet from the PC? Also sometimes trying the different USB slot can help
I’ve tried 2 outlets, they are currently plugged into the same one but they were in different ones before. There’s a couple others closeby I can try as well.
I would just experiment and see if anything you do can fix the issue. You sure you can’t hear this on the thx? If that’s the case try plugging the a90 in where the thx is plugged in and unplug the thx
If worst comes to worse, you could either grab a USB power isolator, or grab a new dac that has balanced (which will help with ground loops)
Genius. will do that. I’m positive. I even cranked it all the way on the 3rd highest gain on the THX and nothing. but u can hear it on all gain settings on the Topping
It does sound like a ground loop to me but just to be sure, potentially try plugging in you audio rig into a laptop thats running off battery. If the sound goes away its basically 100% a ground loop with your PC. If not it may be a defective unit.
Yeah that’s interesting that it only happens on the a90
Yes this can solve the issue fairly easily. From what it sounds like it’s def the PC since the sdac gets it’s power from usb
thank you guys. trying the outlets and switching the DAC around. lets see what happens
Have had that many issues with amp/dac/pc ground loops that I eventually just gave up and went to a fully balanced setup.
I’m almost at that point. whats your setup now?
Some can be so problematic to address lol, that it’s just not worth in the end (although glad this isn’t normally the case)
PC -> D90 -> A90 with balanced interconnects.
A90 gang! lets gooooo! lol
If you can’t fix it, you would want to grab a balanced dac with optical (to pretty much eliminate the possibility of a ground loop since balanced would prevent amp to dac and optical would prevent PC to dac loops if your mobo has optical)