[alsa-devel] Altec Lansing FX5051 mixer

[Clemens Ladisch]

Jeremy Nickurak wrote:
> Clemens Ladisch wrote:
> > Jeremy Nickurak wrote:
> >> The mixer doesn't work at all w/linux kernel 2.6.22, everything is locked
> >> at 100% volume, which is pretty unhelpful, as it's the only way to adjust
> >> the volume. (no analog controls).
> >>     
> >
> > Are there any messages in the system log when you try to change them?
> 
> Nothing in syslog or dmesg.
> 
> > Please show the output of "lsusb -v" for this device.
> 
> ...
>         bmaControls( 0)      0x15
>           Mute
>           Bass
>           Treble
>         bmaControls( 1)      0x02
>           Volume
>         bmaControls( 2)      0x02
>           Volume
>         bmaControls( 3)      0x00
>         bmaControls( 4)      0x00
>         bmaControls( 5)      0x00
>         bmaControls( 6)      0x00

These descriptors say that there is a two-channel volume control that
applies to the front channels, but I guess it really affects all
channels.

Please show the output of "amixer contents" for this card.

> ...
>         HID Device Descriptor:
>           bLength                 9
>           bDescriptorType        33
>           bcdHID               1.00
>           bCountryCode            0 Not supported
>           bNumDescriptors         1
>           bDescriptorType        34 Report
>           wDescriptorLength     172
>           Report Descriptor: (length is 172)
>             Item(Global): Usage Page, data= [ 0x0c ] 12
>                             Consumer
>             Item(Local ): Usage, data= [ 0x01 ] 1
>                             Consumer Control
>             Item(Main  ): Collection, data= [ 0x01 ] 1
>                             Application
>             Item(Global): Usage Page, data= [ 0x0c ] 12
>                             Consumer
>             Item(Local ): Usage, data= [ 0xe2 ] 226
>                             Mute
>             Item(Local ): Usage, data= [ 0xe9 ] 233
>                             Volume Increment
> ...

This describes an input device that reports 'key' presses to the
computer.  I guess the control panel and remote control don't have a
direct effect but expect the computer to explicitly change mixer
controls when a key is pressed.

However, this shouldn't prevent alsamixer from working.

It might be possible that the mixer controls don't have many steps and
that the step size used by alsamixer is so small that the device rounds
the setting back to the old position.  Please try PageUp/Down or Home/
End instead of Up/Down keys.


Regards,
Clemens