Channel distortion when converting S16_LE -> S32_LE ('plug' plugin)

[GitHub issues - opened]

alsa-project/alsa-lib issue #195 was opened from dh1dm:

When using a Terretec EWX2496 (ICE1712) a sample format conversion
is required in some cases as S32_LE is the only supported format.
This can be done by using the 'plug' plugin (e.g. 'plughw:0,0').
However, the left audio channel is distorted in a varying intensity,
it sounds like a resolution loss in the lower bits.
Applications with native S32_LE support (e.g. Audacity) do not show this
effect.
I'd suppose that the responsible code is in 'alsa-lib/src/pcm/pcm_plug.c',
but up to now I could not track down this issue.

Issue URL     : https://github.com/alsa-project/alsa-lib/issues/195
Repository URL: https://github.com/alsa-project/alsa-lib