Intel High Definition Audio
The successor to AC'97, launched by Intel in 2004 under the codename Azalia — the interface behind almost every built-in audio jack on a PC today.
It kept the controller-plus-codec split but raised the ceiling to 192 kHz and 32 bits, with several simultaneous streams in each direction. The real novelty was that codecs describe themselves: the driver reads out a graph of converters, mixers and pins and can change what each jack does. Hence jack detection muting the speakers when headphones go in, and the dialog asking what you just plugged in.
The spec is open enough that one generic driver covers most codecs — Windows has its own, Linux has snd-hda-intel in ALSA. Anything the graph fails to describe ends up as a vendor special case, and the Linux kernel's list of per-motherboard quirks is long. HDMI and DisplayPort audio from graphics cards travels over the same interface.