Red Hat Bugzilla – Bug 856837
ALSA HDA driver and HP onboard sound is causing crackling/popping during volume change in RHEL6
Last modified: 2013-05-20 12:38:03 EDT
Description of problem: I did also some measurement and the ALSA HDA driver tests to eliminate the pops caused by the volume changes (volume slider changes) using a mixer application. I believe that this issue is related directly to hardware and hardware vendor should be asked, why changing of the volume in the HDA audio codec causes pops in the analog output. I can reproduce the clicks with some hardware, but other hardware does not suffer from this issue. I verified the driver and I do not see any problems there. Also, I wrote a script changing the volume periodically using direct HDA codec writes and the pops are there (for some HDA codec types), too. Perhaps, there might be a vendor specific workaround to set the volume without clicks outside the HDA specification from Intel, but also in this case, the hardware vendor (HDA codec vendor, PC vendor) might be asked to provide this information. Version-Release number of selected component (if applicable): 2.6.32-279.2.1.el6.x86_64 How reproducible: Easily on HP onboard sound. Steps to Reproduce: 1. Move volume slider up and donw to change audio volume. Actual results: Volume change with crackling/popping. Expected results: Volume change with no crackling/popping. Additional info: Still narrowing down other affected hardware
The affected platforms are HP Z400 and HP Z800 (the ALC268 audio codec). Also, I can reproduce this behaviour (clicks) using Lenovo T61 laptop (the AD1984 audio codec).
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Hey Jaroslav, Given the importance of this request and it getting nacked for 6.4, can you please nominate this request for 6.4.z? Thanks, -Dan
Actually, there is no solution for these issues as far as I know. The click issues may be related to the hardware implementation. I would keep this bug for a reference and for future comments.
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