[blurb357]

I got a little dot mkii for Christmas, it is hooked up to an audioengine  D1 DAC and is using the original tubes provided. The audioengine D1 is hooked into a USB 3.0 socket on my PC and the little dot mkii is plugged in using a standard 3 prong UK plug into an extension socket. However, whenever I plug it in using an RCA to RCA cable (not while using RCA to 3.5mm) there is prominent distortion and hum that is very loud. I am not sure whether this is a grounding issue or something else. My setting are for low/medium impedance (gain = 5, Switch 1 = on, switch 2 = off. 
 
Would appreciate any help greatly.

 

[blurb357]

Anyone?

 

[yoyojoe]

Try some different RCA cables there might be a short or something. 

 

[blurb357]

Okay, so the distortion is only coming out of the Amp, no distortion when I plug my headphones directly into my DAC. Tested another RCA to RCA cable, doesn't work. I then unplugged the DAC from my PC and plugged it into my laptop, no distortion (MacOS) this has lead me to believe that it may be an issue with the output from the PC. However both the 3.5mm jack and the USB dac created distortion, so either it is hardware to do with my motherboard (ASUS Z170 pro (non gaming edition)), distortion from the energy of the PC, or a software issue within windows itself. Any ideas? BTW this is the sound it makes: https://youtu.be/iXrzfYparsg