On 31.07.2012 12:12, Joao Bonina wrote:
> 
> 
> It doesn't show anything when that happens.

Well, it shows:

[  349.789200] hub 1-0:1.0: port 4 disabled by hub (EMI?), re-enabling...

I guess this about the time when the streaming stops? How does your USB
wiring setup look like and what kind of system is that? Smells like a
hardware issue, to be honest. You could do some stress-testing by
transferring huge amounts of data from one USB storage media to another.
Also try replacing the cables maybe.

I'm Cc'ing the linux-usb list, maybe someone there has an idea.


Daniel


> 
> Looking at dmesg (I'm attaching it), it shows this:
> [  350.170478] usb 1-4: config 1 has an invalid interface number: 3 but max is 2
> [  350.170500] usb 1-4: config 1 has no interface number 2
> [  350.170843] usb 1-4: config 1 has an invalid interface number: 3 but max is 2
> [  350.170864] usb 1-4: config 1 has no interface number 2
> [  350.171344] usb 1-4: New USB device found, idVendor=21b4, idProduct=0230
> 
> [  350.171366] usb 1-4: New USB device strings: Mfr=1, Product=2, SerialNumber=3
> [  350.171385] usb 1-4: Product: Ayre USB Interface
> [  350.171401] usb 1-4: Manufacturer: Ayre Acoustics
> [  350.171418] usb 1-4: SerialNumber: (C) 2010 XMOS/Wavelength Audio
> 
> 
> Don't know if those 'invalid interface number' messages are relevant for the issue.
> 
> Joao
> 
> 
> ----- Original Message -----
> From: Daniel Mack <zonque@gmail.com>
> To: Joao Bonina <bonina_2001@yahoo.com>
> Cc: "alsa-devel@alsa-project.org" <alsa-devel@alsa-project.org>
> Sent: Tuesday, 31 July 2012, 6:24
> Subject: Re: [alsa-devel] Alsa: USB Class 2 Audio soundcard device disappears suddenly
> 
> On 31.07.2012 00:32, Joao Bonina wrote:
>> Hi,
>>
>> I'm using an USB Class 2 Audio DAC (basically a soundcard) with my Linux box and MPD software.
>>
>> It works great when playing files stored in a remote share, but when 
>> playing files from an USB pen, it stops playing in a few minutes.
>>
>> Mpd.log shows this:
>>
>> Code:
>> Jul 30 13:03 : output: "USB" [alsa] failed to play: No such device
>> Jul 30 13:03 : output: closed plugin=alsa name="USB"
>> ALSA lib pcm_hw.c:1401:(_snd_pcm_hw_open) Invalid value for card
>> Jul 30 13:03 : output: Failed to open "USB" [alsa]: Failed to open ALSA device "hw:0,0": No such file or directoryIt seems to be somewhat related to the USB bus not being able to 
>> cope with both PCM streaming to the soundcard and reading from the flash pen simultaneously, I guess.
>>
>> So, anybody faced this issue previously and can provide some hints to solve this?
>>
>> MPD is 0.17, kernel is 3.2.17, alsa-utils is 1.0.25.
> 
> Does the kernel log or 'dmesg' show anything weird what that happens?
> 
> 
> Daniel
>