From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugtrack@alsa-project.org Subject: [ALSA - driver 0000737]: Background noise in master when no playing sound on Asus A7N8X Deluxe (nforce 2) Date: Sat, 9 Apr 2005 17:26:21 +0200 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from bugtrack.alsa-project.org (gate.perex.cz [82.113.61.162]) by alsa.alsa-project.org (ALSA's E-mail Delivery System) with ESMTP id 03E81220 for ; Sat, 9 Apr 2005 17:26:21 +0200 (MEST) Sender: alsa-devel-admin@lists.sourceforge.net Errors-To: alsa-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org The following issue requires your FEEDBACK. ====================================================================== ====================================================================== Reported By: keymon Assigned To: ====================================================================== Project: ALSA - driver Issue ID: 737 Category: PCI - intel8x0 Reproducibility: always Severity: minor Priority: normal Status: feedback Distribution: Debian Kernel Version: 2.6.6 ====================================================================== Date Submitted: 12-21-2004 09:28 CET Last Modified: 04-09-2005 17:26 CEST ====================================================================== Summary: Background noise in master when no playing sound on Asus A7N8X Deluxe (nforce 2) Description: Quoting http://www.nvnews.net/vbulletin/printthread.php?t=35148: Every Asus A7N8X Deluxe Rev 2.0 Board has a problem with a weird "whining" "whirring" or "buzzing" "static" noise coming out of the speakers AND out of the motherboard itself. When speakers are connected and the volume is turned up to normal levels, the noise is very loud, approx 20% of the signal. This noise appear when the card is not playing sound and there is low CPU using. As soon as you play sound, noise stops. If you pause xmms or any player, noise returns. Muting all the channels does not stop the noise, but if you exec: "alsactl power 0 off" &https://bugtrack.alsa-project.org/alsa-bug/view.php?id=161;noise stops!, but you have to exec "alsactl power 0 on" to use the card again. The driver could do the same than "alsactl power 0 off" when it isn't playing sound. If you use the lastest nforce drivers (1.0-0283 or newer) noise stops. ====================================================================== ---------------------------------------------------------------------- tiwai - 12-21-04 18:40 ---------------------------------------------------------------------- Please show /proc/asound/card0/codec97#0/ac97#0-0* files? You can try to flip bits of POWER ac97 register (0x26) by writing to ac97#0-0+regs proc file above such as: # echo 26 803f > /proc/asound/card0/codec97#0/ac97#0-0+regs This feature is enabled only when compiled with debug option (e.g. --with-debug=full). Read the previous value, and change some bits. Try first to turn bit 15 (0x8000) on. This can be an EAPD control. Bit 14 (0x4000) is HP power down, Bit 8 and 9 (0x0300) are ADC/DAC power down. Also, bit 10 is analog mixer (vref). In the power-down code in ac97_codec.c, all these bits are turned on. If it's EAPD, you can control via 'External Amplifier' mixer swithc, too. Other bits are essential, so in general you shouldn't turn off during the operation. ---------------------------------------------------------------------- jdthood - 04-09-05 17:26 ---------------------------------------------------------------------- Submitter: You were asked to provide additional information. Can you please provide it? Issue History Date Modified Username Field Change ====================================================================== 12-21-04 09:28 keymon New Issue 12-21-04 09:28 keymon Distribution => Debian 12-21-04 09:28 keymon Kernel Version => 2.6.6 12-21-04 09:28 keymon Issue Monitored: keymon 12-21-04 18:40 tiwai Note Added: 0002900 04-09-05 17:26 jdthood Note Added: 0004423 04-09-05 17:26 jdthood Status new => feedback ====================================================================== ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click