> I have a pair of powered studio monitors (Mackie MR5), and I completely relate to this problem. Many PCs and phones will emit an audible hissing noise while plugged in. I've tested on a dozen different devices, with integrated and external DACs, five hundred dollar sound cards, massively shielded cables, practically every modern OS you can name, tweaking every audio setting exposed to me. The only devices that work perfectly are (1) my TV output, and (2) every single Apple product.

If almost every device has poor audio quality, maybe its not the device but the headphones that are your problem?