I've been noticing a low repeating pulsing noise (the sound is similar to that static you get when plugging your headphones in) in the left channel of my Audio-GD Fun Version A DAC/AMP.
I am using the device via USB.
After some tinkering around, I have found that the pulsing noise only appears when (bear with me) sound is "playing".
Skype calls, YouTube/Twitch videos, Foobar2000 etc.
The weird thing is, as long as any of the mentioned applications are running, the pulsing noise keeps playing even with the player paused and volume muted (in the case of videos),
and songs paused in Foobar, but dissapears in around 10-20 pulses right after the audio is terminated (that is, when everything is dead silent).
What could be causing this, and how do I fix it?