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Date:   Wed, 03 Mar 2021 20:22:38 +0100
Message-ID: <s5ho8g0avpd.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     John Ernberg <john.ernberg@actia.se>
Cc:     "perex@perex.cz" <perex@perex.cz>,
        "tiwai@suse.com" <tiwai@suse.com>,
        "alsa-devel@alsa-project.org" <alsa-devel@alsa-project.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "kempe@lysator.liu.se" <kempe@lysator.liu.se>
Subject: Re: [PATCH] ALSA: usb: Add Plantronics C320-M USB ctrl msg delay quirk
In-Reply-To: <20210303181405.39835-1-john.ernberg@actia.se>
References: <20210303181405.39835-1-john.ernberg@actia.se>
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On Wed, 03 Mar 2021 19:14:39 +0100,
John Ernberg wrote:
> 
> The microphone in the Plantronics C320-M headset will randomly
> fail to initialize properly, at least when using Microsoft Teams.
> Introducing a 20ms delay on the control messages appears to
> resolve the issue.
> 
> Link: https://gitlab.freedesktop.org/pulseaudio/pulseaudio/-/issues/1065
> Tested-by: Andreas Kempe <kempe@lysator.liu.se>
> Signed-off-by: John Ernberg <john.ernberg@actia.se>
> ---
> 
> Note: Microsoft Teams is the only application tests have been performed with
> and no other kinds of investigations have been performed, like USB packet logging.
> Originally reported as a possible PulseAudio issue, where it was suggested to
> try a delay quirk in the kernel.
> If other tests should be performed, please let me know which tests and I will try to do them.
> 
> All testing was done on 5.10, patch was then applied on sound.git master for submission
> 
> I did not register to the mailing lists, please keep me CC on any comments. Thanks!

Thanks, applied now.

It's a good timing, as I've recently got a bug report for the similar
device (C320) showing mysterious behavior on Teams :)


Takashi