[ANNOUNCE] New Mixer Handling in PA 0.9.16/F12

[Doug Ledford]

On Sat, Aug 01, 2009 at 06:40:12AM +0100, Matthew Garrett wrote:
> On Sat, Aug 01, 2009 at 12:29:36AM -0500, Doug Ledford wrote:
> 
> > That reading in the data digitally uses non trivial amounts of PCI and
> > CPU bandwidth.  If I can't hear the difference between the two modes,
> > then that CPU usage is a total waste of resources.  I have other things
> > I want my CPU to be doing.
> 
> If 150K/sec is non-trivial PCI bandwidth, I think you should probably 
> ask for a refund on your motherboard. From a power management point of 
> view I'd like to agree that offloading this from the CPU is a good 
> thing, but Lennart's right - most newly built machines don't hook these 
> up, and adding a control that influences CD volume on a small number of 
> machines and does nothing whatsoever on a larger number isn't a sensible 
> UI optimisation.

It's also things like erratic output via PA versus smooth output via
analog input.  This particular laptop pops and crackles every time the
PCM starts/stops, while analog signals are much cleaner.  And it would
be pretty easy to have a warn once dialog that tells users that attempt
to adjust the CD in volume that it may not have any effect if the analog
input isn't connected to the sound card or if the cd playback software
skips the analog input in favor of digital data transfer.  You could
even ask users after an adjustment if the adjustment made any
difference, and if it didn't, you could remove it from the UI.