From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Platt Subject: Re: Problem with soundmodem on Eee PC Date: Sat, 12 Sep 2009 16:12:33 -0700 Message-ID: <4AAC2AE1.9090609@radagast.org> References: <984e45570909091532n34cb261hd9cdd6f30d448bf7@mail.gmail.com> <4AA85757.8010105@lightningflash.net> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4AA85757.8010105@lightningflash.net> Sender: linux-hams-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: "J. Lance Cotton" Cc: Julian Moss , linux-hams@vger.kernel.org > 2) Use the ALSA sound system instead of the OSS system, which I think is > now standard on Ubuntu and most other 2.6 Linuxes. I had been sticking > with OSS for a while because I found the commercial (paid) OSS system to > be very stable on the old SuSE distro I was running. I now use Ubuntu > and the ALSA system will re-sample whatever audio comes in from whatever > soundcard to give the software what it asked for. That's true, *if* you specify the "plughw:" ALSA device as the one to use. This utilizes a library plugin which will perform sample-rate and sample-depth conversion on the fly, so that the application will get the rate it expects. If you use the direct "hw:" device specification, the application is restricted to only those exact sample rates / widths / formats that the hardware supports. If the app tries to request an unsupported configuration, the attempt to open the device will fail and the app won't get any audio in/out over the channel. The current version of the soundmodem configurator has "plughw:" available in the menu of device choices for ALSA. It also has some fixes to audio-channel management that are needed with some ALSA devices (e.g. some USB audio converters). Older versions of the soundmodem app may not work well with some devices when using ALSA. I have a feeling that some of the soundmodem utility code (e.g. the scope) may need some of the same "restart cleanly after an error" fixes that the main modem code required, in order to work properly with ALSA.