Subject: Re: setting uhid parameters (mute=1 on Yamaha USB spkrs)?
To: Jonathan Stone <jonathan@DSG.Stanford.EDU>
From: Lennart Augustsson <>
List: current-users
Date: 08/16/2000 08:28:00
Jonathan Stone wrote:

> After battling for days with unsupported soundcards in laptops, I gave
> up and bought some USB speakers: Yamaha YST-MS55D. They look great.
> Unfortunately, the UHID device in the speakers comes with a "Consumer"
> knob for mute, and the mute defaults to "on". I hoped usbhidctl might
> allow setting the mute from 1 to 0, but nppe.

Usually the knobs and the sound producing parts of USB speakers are not
connected at all.  So the setting of a HID button should not matter.  But there
might be exceptions to this, I don't know.

The first thing to try is to use mixerctl to manipulate the mixer in the speaker.

If that doesn't work, usbbhidctl should be fixed so you can actually set items
with it (that fact that you can't is listed as a bug).  Someone was working on this,
but I've forgot who.

> Anyone got any ideas? Does it take anything more complicated than parsing
> the strings ( ala sysctl )and writing ? (I'm an utter USB neophyte).

The usb(3) library provides you with all the tools you need to change a HID control
with a few lines of code.

    -- Lennart