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RE: Interesting analogy, but...

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The more you obstruct anything from getting from point-A to point-B the more jitter you induce on that thing.
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No doubt about that. Just that it is not how computer audio works. The soundcard/USB controller does not care when that thing gets into point B, as long as it gets there on time. In computer audio the point B is almost always a memory location where the data waits (this is called the playback latency), until the soundcard/USB controller reads it via DMA, independently of the CPU (i.e. tasks/scheduler). How does the jitter in process scheduling as analysed by that paper you have linked fit into the picture? I do not see it being involved in the second stage - delivery to the actual DAC. It may affect the spectrum of power supply noise but that is about all.

You are using linux, right? A typical player would be MPD. For PCI cards, in its default configuration the data waits in RAM for the DMA to read for almost half a second since the buffer size is 500ms and period size (IRQ period) 5ms. It means every 5ms MPD makes sure there is approx. 495ms of fresh audio samples ready in RAM for the DMA to read. USB uses lower values since there are hard-coded limits in the USB driver. Raise them (for adaptive mode) and you will get the same values. And I have not ever seen anyone here discussing the buffer_time and period_time parameters in mpd.conf, meaning the defaults are being widely used.

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