Hi Guillaume,
On Tue, Feb 04, 2014 at 06:29:28PM +0100, Guillaume Pellerin wrote:
Sorry Lewis, I was AFK these days. Back now :)
Can you try to add this line to /etc/modprobe.d/alsa-base.conf
options snd_usb_audio vid=0x763 pid=0x2012 device_setup=0x03 enable=1 nrpacks=1
and then:
$ sudo modprobe -r snd-usb-audio
$ sudo modprobe snd-usb-audio
I added your suggested kernel module option line and rebooted my
system for good measure.
$ cat /proc/asound/card0/stream0 # now gives:
M-Audio FastTrack Pro at usb-0000:00:1d.0-2, full speed : USB Audio
Playback:
Status: Stop
Interface 2
Altset 2
Format: S24_3BE
Channels: 2
Endpoint: 3 OUT (ADAPTIVE)
Rates: 44100, 48000
Interface 2
Altset 5
Format: S24_3BE
Channels: 2
Endpoint: 3 OUT (ADAPTIVE)
Rates: 8000 - 48000 (continuous)
$ cat /proc/asound/card0/stream1 # now gives:
M-Audio FastTrack Pro at usb-0000:00:1d.0-2, full speed : USB Audio #1
Playback:
Status: Stop
Interface 3
Altset 2
Format: S24_3BE
Channels: 2
Endpoint: 4 OUT (ADAPTIVE)
Rates: 44100, 48000
Interface 3
Altset 5
Format: S24_3BE
Channels: 2
Endpoint: 4 OUT (ADAPTIVE)
Rates: 8000 - 48000 (continuous)
Capture:
Status: Stop
Interface 4
Altset 2
Format: S24_3BE
Channels: 2
Endpoint: 5 IN (SYNC)
Rates: 8000 - 48000 (continuous)
I've also updated my arecord test command to account for the the
S24_3BE format:
arecord -t raw -f S24_3BE -c2 -r 48000 -D hw:0,1 -vv | aplay -f S24_3BE -c2 -r 48000 -D
hw:0,0
Unfortunately, I am still getting bad captures in about ~10% of my
test cases. I have noticed a slightly different problem in this
configuration: about half of the bad captures are not just a distorted
signal, but instead very loud pure white noise. My ears are still
ringing!
un/replug the card and make your tests again.
I must admit I've almost always use the FTP with JACK so I'm not
completly aware of the behavior of the device without it.
If this has no (good) effect, it could be something between you USB
system and the kernel. I've discover recently that crackles could
raise up on other cards and systems because of a dynamic USB ID
allocation of the kernel. The pb disappeared when the option is
switched off.
So, let's continue if the first ALSA tweak doesn't work..
Regards,
Guillaume
No luck so far, and the mystery continues. Are there specific kernel
configuration options which you would advise disabling? Here is a
snippet from my current /proc/config.gz which shows some settings
related to USB:
# --------------------------------------------
#
# Miscellaneous USB options
#
CONFIG_USB_DEFAULT_PERSIST=y
CONFIG_USB_DYNAMIC_MINORS=y
# CONFIG_USB_OTG is not set
CONFIG_USB_MON=m
CONFIG_USB_WUSB=m
CONFIG_USB_WUSB_CBAF=m
# CONFIG_USB_WUSB_CBAF_DEBUG is not set
# --------------------------------------------
Again, your help on this one is much appreciated!
.lewis