I wonder if this problem could be "solved" by having some kind of "dual mode" DACs that can accept two streams of audio at different sample rates, likely 44.1khz and 48khz, which are converted to analog in parallel and then mixed back together at the analog output.
Then at the operating system level rather than mixing everything to a single audio stream at a single sample rate you group each stream that is at or a multiple of either 44.1khz or 48khz and then finally sends both streams to this "dual dac", thus eliminating the need to resample any 44.1khz or 48khz stream, or even vastly simplifying the resample of any sample rate that is a multiple of this.
> I wonder if this problem could be "solved" by having some kind of "dual mode" DACs that can accept two streams of audio at different sample rates, likely 44.1khz and 48khz, which are converted to analog in parallel and then mixed back together at the analog output.
You'd just resample both at 192kHz and run it into 192kHz DAC. The "headroom" means you don't need to use the very CPU intensive "perfect" resample.
Then at the operating system level rather than mixing everything to a single audio stream at a single sample rate you group each stream that is at or a multiple of either 44.1khz or 48khz and then finally sends both streams to this "dual dac", thus eliminating the need to resample any 44.1khz or 48khz stream, or even vastly simplifying the resample of any sample rate that is a multiple of this.