From mboxrd@z Thu Jan 1 00:00:00 1970 From: Emmanuel Milou Subject: Capture and playabck together Date: Wed, 20 Feb 2008 11:09:25 -0500 Message-ID: <47BC50B5.9020806@savoirfairelinux.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from xenon.savoirfairelinux.net (savoirfairelinux.net [199.243.85.90]) by alsa0.perex.cz (Postfix) with ESMTP id 9C73F244BC for ; Wed, 20 Feb 2008 17:09:06 +0100 (CET) Received: from [192.168.1.216] (dyn216.inside.savoirfairelinux.net [192.168.1.216]) by xenon.savoirfairelinux.net (Postfix) with ESMTP id E64EDF6931 for ; Wed, 20 Feb 2008 11:09:04 -0500 (EST) List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org To: alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org Hi all, I am developping an open-source C++ softphone based on Alsa. We used to use Portaudio but we recently decided to switch to Alsa. I am quite unexperimented in Alsa dev and I got some difficulties to make it work fine. My capture and playback devices are plughw:0,0. I am using read/write transfers. When I disable the capture, playback works fine; when I disable the playback, capture works fine. The problems occurs when I used them together. If I set hardware parameters for both, the playback sound is awful and there is no capture, and finally core dumped. If I set hardware parameters for the playback stream only, the playback works fine, but no capture, I just get an echo with an input/ouput error. Where do you think the problem comes from? Isn't it possible to set hardware configuration for playback and capture? Is there a hardware ring buffer for each stream ? Thanks for your help Manu