No audio at all. I'd have to double-check when it happens again, but the device is listed as an audio output device in the OS, but no audio is played.What is specifically the symptom of the issue you were having? Did your DAC completely stop working, like it was unplugged? Or did it cut out and back in like what I'm describing happens with mine?
The audio cut-out and back in does sound like a hardware issue. I've always had terrible luck with audio gear. My old speakers used to have a volume wheel and that would eventually get a bit dirty, which would continually cause one audio channel to crackle and drop out like you describe. A bit of electrical contact cleaner would help. Or replacing the potentiometer.
And with my current DAC (ifi nano iDSD), I had issues with the 3.5mm headphone jack. Plugging in the headphones into the 3.5mm jack mutes the RCA output for the speakers. But over time (it was only a few months of use), that 3.5mm jack would cause problems when I unplugged it and I would randomly have my left channel drop out on my speakers. I did an RMA on the DAC it quickly did the same thing. So my workaround is just always leave the 3.5mm plugged in, use an audio splitter cable so that the 3.5mm connects to my headphones and speakers and just cut the power to my speakers when I want headphones only.