Created attachment 479163 [details] 2.6.18-238 based patch Description of problem: Customer is using ARX USB I/O[1] soundcards for recording/playback however they're unable to set the mixer levels on the Line-In capture channel. From alsamixer the capture levels cannot be adjusted, and when adjusted from gnome-volume-control the settings do not persist. Using amixer we can see that the levels are not being set properly: # amixer --debug -c 0 set PCM,0 25% cap Simple mixer control 'PCM',0 Capabilities: cvolume cswitch cswitch-joined Capture channels: Front Left - Front Right Limits: Capture 0 - 128 Front Left: Capture 32 [25%] [5.58dB] [on] Front Right: Capture 32 [25%] [5.58dB] [on] # amixer --debug -c 0 get PCM,0 Simple mixer control 'PCM',0 Capabilities: cvolume cswitch cswitch-joined Capture channels: Front Left - Front Right Limits: Capture 0 - 128 Front Left: Capture 1 [1%] [0.00dB] [on] Front Right: Capture 1 [1%] [0.00dB] [on] jkysela pointed me to upstream commit: http://git.alsa-project.org/?p=alsa-kernel.git;a=commit;h=641b4879444c0edb276fedca5c2fcbd2e5c70044 ..which caches mixer values in the usb-audio driver. I've built a test kernel (2.6.18-238 + this patch) which has been confirmed to resolve the issue: https://brewweb.devel.redhat.com/taskinfo?taskID=3114025 Attaching backported patch which applies against 2.6.18-238. Version-Release number of selected component (if applicable): 2.6.18-238.el5 How reproducible: always Steps to Reproduce: 1. amixer --debug -c 0 set PCM,0 25% cap 2. amixer --debug -c 0 get PCM,0 Actual results: capture levels unchanged Expected results: capture levels adjusted Additional info: [1] http://www.arx.com.au/International/audibox_usb_io.htm
Seems reasonable. I'll try to put that together next week. Cheers, Don
in kernel-2.6.18-246.el5 You can download this test kernel (or newer) from http://people.redhat.com/jwilson/el5 Detailed testing feedback is always welcomed.
Technical note added. If any revisions are required, please edit the "Technical Notes" field accordingly. All revisions will be proofread by the Engineering Content Services team. New Contents: Setting the capture levels on the Line-In capture channel when using an ARX USB I/O sound card for recording and playback did not work properly. The set values were not persistent. With this update, the capture values are now cached in the usb-audio driver leaving the set capture levels unchanged.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2011-1065.html