Messages in this thread Patch in this message |  | | From | Pete Zaitcev <> | Subject | Loud screech after reboot of 2.2.18-pre22 | Date | Sun, 19 Nov 2000 15:30:39 -0800 (PST) |
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Hi,
I have a Sony VAIO Z505JE with ymfpci sound and built-in microphone and speaker. Everything worked fine with 2.2.17 plus ymfpci patch, but the 2.2.18-pre22 produces a loud screech starting as sound initializes and ending when startup scrips load mixer settings. This happens because of audio loop between microphone and speakers.
I found that the culprit is the change to values of array mixer_defaults[] in ac97_codec.c, that happened in 2.2.18-pre.
Currently I run the following patch:
--- linux-2.2.18-pre22/drivers/sound/ac97_codec.c Sat Nov 18 19:04:34 2000 +++ linux-2.2.18-pre22-p3/drivers/sound/ac97_codec.c Sun Nov 19 15:37:44 2000 @@ -131,7 +131,7 @@ {SOUND_MIXER_PCM, 0x4343}, {SOUND_MIXER_SPEAKER, 0x4343}, {SOUND_MIXER_LINE, 0x4343}, - {SOUND_MIXER_MIC, 0x4343}, + {SOUND_MIXER_MIC, 0x1111}, /* P3 - audio loop */ {SOUND_MIXER_CD, 0x4343}, {SOUND_MIXER_ALTPCM, 0x4343}, {SOUND_MIXER_IGAIN, 0x4343}, I wonder if there is a better way?
In the interests of full disclosure let me mention that YMFxxx do have internal loopbacks that may produce the same effect and that I checked to the best of my ability that those loopbacks are muted. Therefore I conclude that the loopback happens inside the AC97 (if such a thing is possible).
--Pete - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
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