sox resampling options

Hello,
I would suggest a slightly different behaviour of the upsampling settings, here some examples :
-if I listen to 44.1khz, then I would like to upsample to a multiple 88.2k if the DAC supports 96k max or 176.4k if the DAC supports 192khz.
-if I listen to 48khz, then I would like to upsample to a multiple 96k if the DAC supports it or 192khz if the DAC supports it.
-if I listen to 176.4khz, then I would like to downsample to a multiple 88.2k if the DAC supports 96k max
if the DAC does not support some exotic frequencies, fallback to the max supported.

I see 4 nice set-it-forget-it possible behaviours :
“over-sample/down-sample to max supported by the DAC”
“No over-sampling (Bit-perfect) / down-sample to max supported by the DAC”
“No over-sampling (Bit-perfect) / down-sample with x1/8 , x1/4 , x1/2”
“upsample with x2, x4, x8 / downsample with x1/8 , x1/4 , x1/2”
“fix : 44.1khz / 48khz / … / 384khz”

Of course, keeping the quality setting of the SRC.

However, if I remember well, the bit depth is a low value-added setting (almost unuseful).
Indeed any modern DAC working internally at 24-bits or 32-bits are able to add zeros to 16-bits or 24bits signals.
If done well, there is a little value added to do the down conversion from 32-bits to 24-bits or 24bits to 16bits. Almost any DAC would only take the significant bits and omit the least significant.

Furthermore in practice, changing the upsampling from the web interface is very slow, and stops the update of MPD (connected to a NAS)!

Maybe I’m ignorant, but how to detect the DAC capabilities?
And I made a plugin to resample all source in volumio (not only mpd). It very fast to change settings. But it is experimental…
If you want to test, do not use resampling in volumio.
https://github.com/balbuze/volumio-plugins/tree/master/plugins/audio_interface/volgrp