1 correction though: You claim “you can't rely on ALSA as it will take control of the entire sound device, so you can only use it to handle one application at a time. So no hardware multiplexing.”

That’s false. I remember my main advantage switching from OSS to ALSA was being to play 2 apps at the same time. I still feel like #PulseAudio is the new kid on the block—now I feel old👴

https://en.wikipedia.org/wiki/Advanced_Linux_Sound_Architecture explicitly lists “Hardware mixing of multiple channels.” as a feature.

software framework

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