Does Volumio do upsampling of some kind

i am having a strange situation here. There is this particular stream:

when I add it to volumio (3.179) and play the stream, volumio show it playing at around 32kbps (yes I mean 32kbps, not 32kHz). The stream actually sounds pretty decent for such low bit rate (on speakers, have not tested through headphones). But here is the strange thing: my SMSL Sanskrit 10th V2 DAC shows a sample rate of 96kHz on the display! a 96Khz sample rate on a 32kbps bit rate? You would expect such a stream to sound pretty lousy, wouldn’t you?

When I load the stream into VLC on Ubuntu 18, this is what VLC reports:

Codec: MPEG AAC Audio (mp4a)
Type: Audio
Channels: Stereo
Sample rate: 32000 Hz
Bits per sample: 32
AAC extension: SBR
Content bitrate: 32kb/s (changes occasionally)

That looks like it makes a lot more sense.

In the case of other network streams, I don’t have this odd phenomenon. No resampling configured in the Volumio UI. Could there be anything in Volumio that explains this?

ETA: when I check the contents of /proc/asound/card5/pcm0p/sub0/hw_params, this is what I see:

format: S32_LE
subformat: STD
channels: 2
rate: 96000 (96000/1)
period_size: 12000
buffer_size: 48003

I.e. it is not the DAC itself upscaling the stream. ALSA controls the sample rate here.

Well, there is a setting for it in Volumio. Check this to see if you have it enabled.

Like I said in my first post: no resampling configured:

ETA: I enabled resampling, then disabled it again. No change.

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I checked the manual of my DAC, and it does not support 32kHz PCM over USB. So that might be the issue here.

How does Volumio process streams when the DAC does not support parameters of the stream?