From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Mack Subject: Re: UAC2 clock selector for AudioBox 1818VSL Date: Thu, 06 Sep 2012 22:53:01 +0200 Message-ID: <50490D2D.3060207@gmail.com> References: <76bd1b6473c857ddd3160280e278e4fb.squirrel@master.museresearch.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-bk0-f51.google.com (mail-bk0-f51.google.com [209.85.214.51]) by alsa0.perex.cz (Postfix) with ESMTP id F043D261616 for ; Thu, 6 Sep 2012 22:53:08 +0200 (CEST) Received: by bkuw5 with SMTP id w5so870160bku.38 for ; Thu, 06 Sep 2012 13:53:08 -0700 (PDT) In-Reply-To: <76bd1b6473c857ddd3160280e278e4fb.squirrel@master.museresearch.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: alsa-devel@alsa-project.org Cc: louis@museresearch.com List-Id: alsa-devel@alsa-project.org Hi, On 06.09.2012 22:20, louis@museresearch.com wrote: > Hi! > I'm attempting to get the "Clock Selector" mixer control to work with > the PreSonus AudioBox 1818VSL (a UAC2 device). > > The control shows up in amixer as an enumerated value, but I don't seem to > be able to set it (I've tried amixer, alsactl, and setting it > programmatically). The possible values are correct (listing Internal > Clock, S/PDIF Clock, and ADAT Clock as possible options); It just doesn't > appear to take my setting, by which I mean amixer doesn't update the > settings, I still have the occasional click when the sampling rates match > over S/PDIF and I attempt to use external sync. No error is returned. > > After digging around USB specs and ALSA's usb/mixer.c and being unfamiliar > with both the USB audio spec and the inner workings of ALSA, I thought > it'd be best to ask the list about this: How would I check to see if ALSA > is asking the device to change clock source at all? Hmm. A clock selector is handled like any other control entity on the hardware. Some thoughts: - Are you able to control other settings like the volume? - It's fairly common for devices to not accept a new clock source setting if they can't lock to the external source within some time. Did you connect anything to the digital inputs? - Are you able to control that setting with the native Mac OS X driver? (IOW, without installing a 3rd-party driver) Also, please send the output of "lsusb -v" for that device. Daniel