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On Sunday, 3 January 2021 15:59:49 GMT Dr Rainer Woitok wrote: |
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> Greetings, |
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> |
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> immediately after a reboot I can clearly hear the white noise created by |
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> executing |
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> |
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> $ aplay /usr/share/sounds/alsa/Noise.wav |
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> Playing WAVE '/usr/share/sounds/alsa/Noise.wav' : Signed 16 bit Little |
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> Endian, Rate 48000 Hz, Mono $ |
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> |
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> and the "lsmod" command lists quite a few loaded sound modules. Howev- |
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> er, after resuming from hibernation the same "aplay" command still pro- |
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> duces the same line on standard output, returns the same exit code of 0, |
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> but does not produce any sound. And the "lsmod" command still lists the |
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> same loaded modules. |
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> |
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> Anybody having a clue what's happening here? |
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> |
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> And while we are at it: At |
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> |
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> https://wiki.gentoo.org/wiki/Kernel/Gentoo_Kernel_Configuration_Guide |
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> |
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> the authors flatly state "Note that ALSA is an exception to the suggest- |
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> ed scheme of not building things as modules: ALSA is actually much easi- |
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> er to configure when the components are modular." without giving any |
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> further expanation. What precisely am I giving away when I build the |
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> ALSA stuff directly into the kernel? |
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> |
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> Sincerely, |
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> Rainer |
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It used to be the case modules were probed/reloaded by 'alsactl init' when |
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initialising the audio card. If built in the kernel binary the command |
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couldn't do this. Troubleshooting required monitoring responses and errors as |
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the modules were being loaded and consequently the devs were not very |
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forthcoming with solutions, unless you had your alsa drivers compiled as |
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modules. |
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|
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I had a laptop a long time ago, which I had to reboot into MSWindows to get |
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the audio to work again. Using alsamixer and alsactl in Linux would not wake |
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up the card, no matter what I tried. One day this problem went away after a |
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kernel update, so I attributed it to a buggy linux audio driver. |
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|
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Some modules show power saving features with 'modinfo', which may alter the |
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card's behaviour if they can be switched off. |
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|
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I suggest you use alsactl init before and after and compare the output between |
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a working and non-working state, to try to isolate the problem. |
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