From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: -32 broken pipe
Date: Fri, 15 Oct 2010 09:51:09 +0200
Message-ID: <4CB807ED.8040205@ladisch.de>
References: <AANLkTim_sdgs0VAU1Ncse9h8a+-3rsB9WbXCQBibdG8B@mail.gmail.com>
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To: Cem ERGEN <cemergen@gmail.com>
Cc: alsa-devel@alsa-project.org
List-Id: alsa-devel@alsa-project.org

(please don't create new threads for the same topic)

Cem ERGEN wrote:
> i've 8 hubs and each hubs has got 4 usb soundcards,

With 16-bit samples at 48 kHz, a full-speed bus has just barely enough
bandwidth for one stream with eight channels, or seven on-channel
streams.

Due to bugs in the EHCI driver, using multiple full-speed audio devices
connected to one or more high-speed hubs connected to one controller is
likely to fail.

Try using multiple controllers, and forcing the hubs to work at full
speed by unloading the ehci_hcd module.


Regards,
Clemens