arv <arvindhandroidin <at> gmail.com> writes: > > Hi All, > > I am trying to playback audio from Android phone using USB AOAv2. (PCM > audio, 16bit, 44.1 KHz, stereo) on a Wandboard Quad (i.MX6) board running > Ubuntu 14.04. > > The detection of phone is fine and playback via alsa commands/gstreamer is > successful. > But during playback, there are distortions in the sound. > > dmesg prints as follows, > retire_capture_urb: x callbacks suppressed ----->[x is around 41 to 300] > retire_capture_urb: x callbacks suppressed > retire_capture_urb: x callbacks suppressed > retire_capture_urb: x callbacks suppressed > > arecord command prints underrun occurred. > > So each time, retire_capture_urb is printed, there is a distortion. > > I tried the same program on different machines. > Following are the results, > On Wandboard, the distortions happen each 40 seconds or so. > On a Linux server PC running Ubuntu 14.04 the audio breaks are more frequent. > On a Linux PC running Ubuntu 12.02 the audio breaks are less frequent. > > Could anyone guide me on how retire_capture_urb be prevented or how can a > smooth playback be achieved ? > > Should there be any special configurations done at USB driver ? > > lsusb -v print is as follows, The synch type for the endpoint appears to be > enumerated as Synchronous. Could the synch type be modified using libusb, is > this the cause of underrun? > > Bus 001 Device 004: ID 18d1:2d02 Google Inc. > Device Descriptor: > bLength 18 > bDescriptorType 1 > bcdUSB 2.00 > bDeviceClass 0 (Defined at Interface level) > bDeviceSubClass 0 > bDeviceProtocol 0 > bMaxPacketSize0 64 > idVendor 0x18d1 Google Inc. > idProduct 0x2d02 > bcdDevice ff.ff > iManufacturer 1 motorola > iProduct 2 MotoG3-TE > iSerial 3 ZY222WB7TT > bNumConfigurations 1 > Configuration Descriptor: > bLength 9 > bDescriptorType 2 > wTotalLength 110 > bNumInterfaces 2 > bConfigurationValue 1 > iConfiguration 0 > bmAttributes 0x80 > (Bus Powered) > MaxPower 500mA > Interface Descriptor: > bLength 9 > bDescriptorType 4 > bInterfaceNumber 0 > bAlternateSetting 0 > bNumEndpoints 0 > bInterfaceClass 1 Audio > bInterfaceSubClass 1 Control Device > bInterfaceProtocol 0 > iInterface 0 > AudioControl Interface Descriptor: > bLength 10 > bDescriptorType 36 > bDescriptorSubtype 1 (HEADER) > bcdADC 1.00 > wTotalLength 40 > bInCollection 2 > baInterfaceNr( 0) 0 > baInterfaceNr( 1) 1 > AudioControl Interface Descriptor: > bLength 12 > bDescriptorType 36 > bDescriptorSubtype 2 (INPUT_TERMINAL) > bTerminalID 1 > wTerminalType 0x0201 Microphone > bAssocTerminal 0 > bNrChannels 2 > wChannelConfig 0x0003 > Left Front (L) > Right Front (R) > iChannelNames 0 > iTerminal 0 > AudioControl Interface Descriptor: > bLength 9 > bDescriptorType 36 > bDescriptorSubtype 3 (OUTPUT_TERMINAL) > bTerminalID 3 > wTerminalType 0x0101 USB Streaming > bAssocTerminal 2 > bSourceID 2 > iTerminal 0 > AudioControl Interface Descriptor: > bLength 9 > bDescriptorType 36 > bDescriptorSubtype 6 (FEATURE_UNIT) > bUnitID 2 > bSourceID 1 > bControlSize 2 > bmaControls( 0) 0x00 > bmaControls( 0) 0x00 > iFeature 0 > Interface Descriptor: > bLength 9 > bDescriptorType 4 > bInterfaceNumber 1 > bAlternateSetting 0 > bNumEndpoints 0 > bInterfaceClass 1 Audio > bInterfaceSubClass 2 Streaming > bInterfaceProtocol 0 > iInterface 0 > Interface Descriptor: > bLength 9 > bDescriptorType 4 > bInterfaceNumber 1 > bAlternateSetting 1 > bNumEndpoints 1 > bInterfaceClass 1 Audio > bInterfaceSubClass 2 Streaming > bInterfaceProtocol 0 > iInterface 0 > AudioStreaming Interface Descriptor: > bLength 7 > bDescriptorType 36 > bDescriptorSubtype 1 (AS_GENERAL) > bTerminalLink 1 > bDelay 1 frames > wFormatTag 1 PCM > AudioStreaming Interface Descriptor: > bLength 11 > bDescriptorType 36 > bDescriptorSubtype 2 (FORMAT_TYPE) > bFormatType 1 (FORMAT_TYPE_I) > bNrChannels 2 > bSubframeSize 2 > bBitResolution 16 > bSamFreqType 1 Discrete > tSamFreq[ 0] 44100 > Endpoint Descriptor: > bLength 9 > bDescriptorType 5 > bEndpointAddress 0x81 EP 1 IN > bmAttributes 13 > Transfer Type Isochronous > Synch Type Synchronous > Usage Type Data > wMaxPacketSize 0x0100 1x 256 bytes > bInterval 4 > bRefresh 0 > bSynchAddress 0 > AudioControl Endpoint Descriptor: > bLength 7 > bDescriptorType 37 > bDescriptorSubtype 1 (EP_GENERAL) > bmAttributes 0x01 > Sampling Frequency > bLockDelayUnits 1 Milliseconds > wLockDelay 1 Milliseconds > Device Qualifier (for other device speed): > bLength 10 > bDescriptorType 6 > bcdUSB 2.00 > bDeviceClass 0 (Defined at Interface level) > bDeviceSubClass 0 > bDeviceProtocol 0 > bMaxPacketSize0 64 > bNumConfigurations 1 > Device Status: 0x0000 > (Bus Powered) > > Thanks for the help.. > > Hi All, Adding to the previous message, I execute the following commands arecord -f cd -v -D plug:hw:3 | aplay -f cd -v -D plug:hw:0 and the prints are as follows, Recording WAVE 'stdin' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo:hw:0 Plug PCM: Hardware PCM card 3 'MotoG3-TE' device 0 subdevice 0 Its setup is: stream : CAPTURE access : RW_INTERLEAVED format : S16_LE subformat : STD channels : 2 rate : 44100 exact rate : 44100 (44100/1) msbits : 16 buffer_size : 22050 period_size : 5513 period_time : 125011 tstamp_mode : NONE period_step : 1 avail_min : 5513 period_event : 0 start_threshold : 1 stop_threshold : 22050 silence_threshold: 0 silence_size : 0 boundary : 1445068800 appl_ptr : 0 hw_ptr : 0 Playing WAVE 'stdin' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo Plug PCM: Hardware PCM card 0 'imx6-wandboard-sgtl5000' device 0 subdevice 0 Its setup is: stream : PLAYBACK access : RW_INTERLEAVED format : S16_LE subformat : STD channels : 2 rate : 44100 exact rate : 44100 (44100/1) msbits : 16 buffer_size : 16384 period_size : 4096 period_time : 92879 tstamp_mode : NONE period_step : 1 avail_min : 4096 period_event : 0 start_threshold : 16384 stop_threshold : 16384 silence_threshold: 0 silence_size : 0 boundary : 1073741824 appl_ptr : 0 hw_ptr : 0 underrun!!! (at least 0.967 ms long) Status: state : XRUN trigger_time: 3093.357585367 tstamp : 3093.367235700 delay : 0 avail : 16384 avail_max : 16384 underrun!!! (at least 0.863 ms long) Status: state : XRUN trigger_time: 3189.419589045 tstamp : 3189.428212045 delay : 0 avail : 16384 avail_max : 16384 hw:0 buffer is less than hw:3 buffer. is it why underrun happens? I couldn't increase it beyond 16384... Thanks for the help. ------------------------------------------------------------------------------ > What NetFlow Analyzer can do for you? Monitors network bandwidth and traffic > patterns at an interface-level. Reveals which users, apps, and protocols are > consuming the most bandwidth. Provides multi-vendor support for NetFlow, > J-Flow, sFlow and other flows. Make informed decisions using capacity planning > reports.http://sdm.link/zohodev2dev > ------------------------------------------------------------------------------ What NetFlow Analyzer can do for you? Monitors network bandwidth and traffic patterns at an interface-level. Reveals which users, apps, and protocols are consuming the most bandwidth. Provides multi-vendor support for NetFlow, J-Flow, sFlow and other flows. Make informed decisions using capacity planning reports.http://sdm.link/zohodev2dev _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
