First of all, ignore_dB=1 *isn't* a fix. This is hardware issue that
can be worked around in linux or pulseaudio, but the proper place to
do it is in linux -- the sound driver.
Second, ignore_dB=1 is a rather poor universal workaround. This is the
problem with bug reports: people see a comment and assume it applies
to everyone's hardware. Wrong. In your specific case, you want to use
the control parameter, which is passed to module-alsa-sink and
module-alsa-source in /etc/pulse/default.pa (or ~/.pulse/default.pa),
load-module module-alsa-sink control=PCM
At that point, PA only controls your PCM mixer control and ignores the
others. That's very different from ignore_dB=1, which simply tells PA
to ignore what linux tells it for the hardware volume range but
continues to adjust all the mixer controls.