On Wed, 2016-10-19 at 19:03 +0200, Oddbjørn Norstrand wrote: > Hi > > I am having problems recording from digital input on a Creative Sound > Blaster X-FI HD. Recordings work using alsa, but I only receive > samples with value zero when using pulseaudio. > > This is the source from pacmd list-sources: > index: 3 > name: <alsa_input.usb-Creative_Technology_USB_Sound_Blaster_HD_000000tf-00.iec958-stereo> > driver: <module-alsa-card.c> > flags: HARDWARE DECIBEL_VOLUME LATENCY DYNAMIC_LATENCY > state: RUNNING > suspend cause: > priority: 9048 > volume: front-left: 65634 / 100% / 0.04 dB, front-right: 65634 / 100% / 0.04 dB > balance 0.00 > base volume: 65536 / 100% / 0.00 dB > volume steps: 65537 > muted: no > current latency: 0.17 ms > max rewind: 0 KiB > sample spec: s16le 2ch 44100Hz > channel map: front-left,front-right > Stereo > used by: 1 > linked by: 1 > configured latency: 40.00 ms; range is 0.50 .. 2000.00 ms > card: 1 <alsa_card.usb-Creative_Technology_USB_Sound_Blaster_HD_000000tf-00> > module: 7 > properties: > alsa.resolution_bits = "16" > device.api = "alsa" > device.class = "sound" > alsa.class = "generic" > alsa.subclass = "generic-mix" > alsa.name = "USB Audio #1" > alsa.id = "USB Audio" > alsa.subdevice = "0" > alsa.subdevice_name = "subdevice #0" > alsa.device = "1" > alsa.card = "2" > alsa.card_name = "USB Sound Blaster HD" > alsa.long_card_name = "Creative Technology USB Sound Blaster HD at usb-0000:00:14.0-2, full speed" > alsa.driver_name = "snd_usb_audio" > device.bus_path = "pci-0000:00:14.0-usb-0:2:1.0" > sysfs.path = "/devices/pci0000:00/0000:00:14.0/usb2/2-2/2-2:1.0/sound/card2" > udev.id = "usb-Creative_Technology_USB_Sound_Blaster_HD_000000tf-00" > device.bus = "usb" > device.vendor.id = "041e" > device.vendor.name = "Creative Technology, Ltd" > device.product.id = "3232" > device.product.name = "USB Sound Blaster HD" > device.serial = "Creative_Technology_USB_Sound_Blaster_HD_000000tf" > device.string = "iec958:2" > device.buffering.buffer_size = "352800" > device.buffering.fragment_size = "176400" > device.access_mode = "mmap+timer" > device.profile.name = "iec958-stereo" > device.profile.description = "Digital Stereo (IEC958)" > device.description = "USB Sound Blaster HD Digital Stereo (IEC958)" > alsa.mixer_name = "USB Mixer" > alsa.components = "USB041e:3232" > module-udev-detect.discovered = "1" > device.icon_name = "audio-card-usb" > ports: > iec958-stereo-input: Digital Input (S/PDIF) (priority 0, latency offset 0 usec, available: unknown) > properties: > > active port: <iec958-stereo-input> > > When I configure the the sound card to off in tab Configuration in > pavucontrol this command works giving me a out.wav file with nonzero > samples. > ffmpeg -f alsa -i hw:2,1 -t 30 out.wav > > When I configure the digital input in pavucontrol and try this command > I get a recording where all samples are zero. > parec --device=alsa_input.usb-Creative_Technology_USB_Sound_Blaster_HD_000000tf-00.iec958-stereo --format=s16le --rate=44100 --channels=2 > samples > > Can anyone see what is wrong or help me further investigate the > problem? This is pretty weird. It really looks like it should be working. Maybe it's a mixer issue? That doesn't seem likely, but I don't have any other ideas. So, start recording with parec, and while it's running, save the output from "amixer -c2" and "pactl list". Then, stop parec, set the card profile to "off" and start recording with ffmpeg. Save the output from "amixer -c2" again. Then send the amixer and pactl output. "pactl list" will be so big that it's best to either upload it somewhere where I can download it from, or attach it as a compressed file. -- Tanu
