Since I replaced my GPU last year, I've noticed that my audio has had hissing and other noise when the computer is under load. I assume it's electrical interference between the motherboard's audio chip and the rest of the board. At some point I'd like to do something about it, but I know very little about audio equipment, the data are hard to quantify, and my perception of the topic is that audiophiles are an endless fount of bullshit that makes it hard to learn anything concrete.
As I see it, I have three possible solutions:
>a dedicated sound card
>an external DAC
>a higher-end mobo
I include a motherboard on the list since I plan to grab a R7 5800X or X3D at the end of this year to replace my R5 3600, and I'd move the 3600 into a secondary machine. I'll already be buying a motherboard for that, so if a better motherboard would solve the problem (presumably having both a better audio circuit, and more stable/isolated circuitry overall), then instead of getting some cheap B450 for the 3600, I might keep the 3600 in my current one and get a better board for the 5800. But I don't know if I'd see any significant difference, at least not without going way overbudget. On the other hand, I don't know if a better motherboard might be worth it in other ways for the 5800.
I'd be wanting to spend less than $100 on this (or, for the motherboard option, $100 over what I'd be spending anyway). But for the three options I don't have a good understanding of the cost-vs-performance value, and the strengths and weaknesses of each, both in general and within my specific budget range.
For reference, my current board is an Asus Tuf B550-Plus (so the lower-tier chipset, and a mid-tier board within that chipset, compared to e.g. Asus's own Strix line). The headphones I'd be plugging into whatever I get are the Sennheiser HD569. Also, I'm on Linux rather than Windows, so drivers/firmware/etc are a potential issue to consider.