From owner-freebsd-current@FreeBSD.ORG Wed Sep 19 06:17:25 2012 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id D583D106564A; Wed, 19 Sep 2012 06:17:25 +0000 (UTC) (envelope-from sendtomatt@gmail.com) Received: from mail-pb0-f54.google.com (mail-pb0-f54.google.com [209.85.160.54]) by mx1.freebsd.org (Postfix) with ESMTP id A000C8FC14; Wed, 19 Sep 2012 06:17:25 +0000 (UTC) Received: by pbbrp2 with SMTP id rp2so1860434pbb.13 for ; Tue, 18 Sep 2012 23:17:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; bh=nAoXzqUCEb4KP/RpKOHk8sW5NYXMLieEZ7TkWNRPAEQ=; b=DCIwdQ2AVaLSJL5zMhlmd4euu5bSiKu+KuKKOVWnMZpRdXwYw6xkUjJhhggK5yzJER E19xGBA4mRYNSRkp2wtQrCZffEK6iwPbieoDnbQueZXk0LzXTrA89c4EkHyGhyTHZxat WQO9txuYCG4F5ehUz1hbRMq/LGfrXWzTwP5a2fpoXne18fE57p7L0c3tNJz40GAXjriP MTdRjKGiX/Ef6yVrGtSQcCqP4ThUq9F7vWkNmWFm0zRBSt/WuHTDfE3zwyPeFH9SDnfr b1zaMylZfUrujb1YIuGMSDas5NFqIa1q16VyHth+vzsFC7kAjiWlPOcgEqBdFxFkYZhk 0SbQ== Received: by 10.68.239.5 with SMTP id vo5mr4710451pbc.102.1348035445093; Tue, 18 Sep 2012 23:17:25 -0700 (PDT) Received: from flatline.local (70-36-223-239.dsl.dynamic.sonic.net. [70.36.223.239]) by mx.google.com with ESMTPS id gj9sm1283931pbc.16.2012.09.18.23.17.22 (version=SSLv3 cipher=OTHER); Tue, 18 Sep 2012 23:17:24 -0700 (PDT) Message-ID: <5059636B.4020902@gmail.com> Date: Tue, 18 Sep 2012 23:17:15 -0700 From: matt User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:15.0) Gecko/20120912 Thunderbird/15.0.1 MIME-Version: 1.0 To: Doug Barton References: <5059194F.4090002@FreeBSD.org> <50595E93.9080908@gmail.com> <50595F83.9030008@FreeBSD.org> In-Reply-To: <50595F83.9030008@FreeBSD.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-current@FreeBSD.org Subject: Re: squealing/whistling audio X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 19 Sep 2012 06:17:26 -0000 On 09/18/12 23:00, Doug Barton wrote: > On 9/18/2012 10:56 PM, matt wrote: >> On 09/18/12 18:01, Doug Barton wrote: >>> Sometime in the last couple of months an old problem has resurfaced on >>> HEAD, a sort of squealing/whistling sound in the audio, even without >>> anything playing. The sound is similar to the wind whistling through >>> something. >>> >>> Before I blindly go off on a bisecting spree, does anyone have a >>> suggestion as to where I might look? >>> >>> Doug >>> >>> >> Electrically that's usually oscillation (too high gain or too much >> electrical feedback) or an unshielded input. > Sorry, I should have been more clear. This problem doesn't occur in > windows, or linux, and last time I checked, didn't occur in freebsd 8. I > have everything irrlevant zeroed out in mixer. > > Doug > It was worth a shot. It is possible that each OS (and version) is setting the associations up properly though except HEAD on your machine. Is it a laptop or a desktop board? Any difference in the nid configuration between freebsd 8 and HEAD? Does changing any of the hw.snd sysctls (latency, exact rate, vpc_0db) have any effect on the sound? http://freshbsd.org/commit/freebsd/r230551 might be worth a look. I couldn't find anything newer that looked like it would have an effect. Their are some earlier commits around January that are dealing with signal gain that could also have an effect. Otherwise, I'm not sure where else to look. Matt