[kalleboo]

Anything inside the case will have more noise from other components than something sitting outside the case. Instead of a sound "card", you're going to want a USB DAC. It doesn't even have to be that expensive - those $10 Apple USB-C dongles were highly rated.

[nicolaslem]

It is mind-boggling how good the Apple dongle is, that something that tiny contains a good DAC and a headphones amplifier. I switch back and forth multiple times a day between the Apple dongle and a Universal Audio interface that cost many times more and I have never heard a difference.

However I hear a big difference with my laptop onboard audio and off brand dongles, they have an audible noise floor.

To the OP I would recommend getting the Apple USB-C dongle before spending big bucks on something else because for listening it's likely to be good enough.

[comprev]

Somewhere here on HN a few years back there was a submission regarding a tear-down of the Apple Lightning to 3.5mm headphones adapter.

The findings concluded the product was insanely good value for money and was on par with mid/high end DAC.

[tensility]

Not if the audio circuitry has been properly canned (i.e. Faraday-caged) and if the power supply produces clean input power; however, one or both and especially the latter often do get compromised in poorly integrated Wintel PC systems.