i am having a strange situation here. There is this particular stream:
http://ice5.securenetsystems.net/WXYG
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:
access: MMAP_INTERLEAVED
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.
