On Sun, 28 Oct 2018 17:55:12 +0100, Alex Stanoev wrote: > > The Creative Audigy SE (SB0570) card currently exhibits an audible pop > whenever playback is stopped or resumed, or during silent periods of an > audio stream. Initialise the IZD bit to the 0 to eliminate these pops. > > The Infinite Zero Detection (IZD) feature on the DAC causes the output > to be shunted to Vcap after 2048 samples of silence. This discharges the > AC coupling capacitor through the output and causes the aforementioned > pop/click noise. > > The behaviour of the IZD bit is described on page 15 of the WM8768GEDS > datasheet: "With IZD=1, applying MUTE for 1024 consecutive input samples > will cause all outputs to be connected directly to VCAP. This also > happens if 2048 consecutive zero input samples are applied to all 6 > channels, and IZD=0. It will be removed as soon as any channel receives > a non-zero input". I believe the second sentence might be referring to > IZD=1 instead of IZD=0 given the observed behaviour of the card. > > This change should make the DAC initialisation consistent with > Creative's Windows driver, as this popping persists when initialising > the card in Linux and soft rebooting into Windows, but is not present on > a cold boot to Windows. > > Signed-off-by: Alex Stanoev <alex@xxxxxxxxxxxx> Applied (with Cc to stable) now. Thanks. Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
