Interesting. I've converted that file to 44100 Hz and now it reveals a strange behavior. When I play it with buffer size of 64 it sounds like the pitch is lower than it should be (even if it doesn't overrun though it does from time to time). When the size is 128 it sounds fine.
# aplay -D plughw:CARD=CA0106 -v --buffer-size=64 /tmp/kde44100.wav Playing WAVE '/tmp/kde44100.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo Plug PCM: Rate conversion PCM (48000, sformat=S16_LE) Converter: libspeex (builtin) Protocol version: 10002 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 : 58 period_size : 14 period_time : 333 tstamp_mode : NONE period_step : 1 avail_min : 14 period_event : 0 start_threshold : 58 stop_threshold : 58 silence_threshold: 0 silence_size : 0 boundary : 4179340454199820288 Slave: Hardware PCM card 0 'CA0106' device 0 subdevice 0 Its setup is: stream : PLAYBACK access : MMAP_INTERLEAVED format : S16_LE subformat : STD channels : 2 rate : 48000 exact rate : 48000 (48000/1) msbits : 16 buffer_size : 64 period_size : 16 period_time : 333 tstamp_mode : NONE period_step : 1 avail_min : 16 period_event : 0 start_threshold : 64 stop_threshold : 64 silence_threshold: 0 silence_size : 0 boundary : 4611686018427387904 appl_ptr : 0 hw_ptr : 0 underrun!!! (at least 0.116 ms long) Status: state : XRUN trigger_time: 301642.243139271 tstamp : 301642.243254519 delay : 2 avail : 56 avail_max : 56 # aplay -D plughw:CARD=CA0106 -v --buffer-size=128 /tmp/kde44100.wav Playing WAVE '/tmp/kde44100.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo Plug PCM: Rate conversion PCM (48000, sformat=S16_LE) Converter: libspeex (builtin) Protocol version: 10002 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 : 117 period_size : 29 period_time : 666 tstamp_mode : NONE period_step : 1 avail_min : 29 period_event : 0 start_threshold : 117 stop_threshold : 117 silence_threshold: 0 silence_size : 0 boundary : 4215369251218784256 Slave: Hardware PCM card 0 'CA0106' device 0 subdevice 0 Its setup is: stream : PLAYBACK access : MMAP_INTERLEAVED format : S16_LE subformat : STD channels : 2 rate : 48000 exact rate : 48000 (48000/1) msbits : 16 buffer_size : 128 period_size : 32 period_time : 666 tstamp_mode : NONE period_step : 1 avail_min : 32 period_event : 0 start_threshold : 128 stop_threshold : 128 silence_threshold: 0 silence_size : 0 boundary : 4611686018427387904 appl_ptr : 0 hw_ptr : 0 This pitch (or maybe speed?) weirdness occurs only on playing stereo files with rate of 44100. I've tried playing music and it indeed sounds a bit transposed. Bufsize of 128 frames also seems to produce underruns after some time, my testing clip was too small to reveal it. So it required bufsize 512 to be played completely without underruns: # aplay -D plughw:CARD=CA0106 -v --buffer-size=512 /tmp/ksp44100.wav Playing WAVE '/tmp/ksp44100.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo Plug PCM: Rate conversion PCM (48000, sformat=S16_LE) Converter: libspeex (builtin) Protocol version: 10002 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 : 529 period_size : 132 period_time : 3000 tstamp_mode : NONE period_step : 1 avail_min : 132 period_event : 0 start_threshold : 529 stop_threshold : 529 silence_threshold: 0 silence_size : 0 boundary : 4764808405757984768 Slave: Hardware PCM card 0 'CA0106' device 0 subdevice 0 Its setup is: stream : PLAYBACK access : MMAP_INTERLEAVED format : S16_LE subformat : STD channels : 2 rate : 48000 exact rate : 48000 (48000/1) msbits : 16 buffer_size : 576 period_size : 144 period_time : 3000 tstamp_mode : NONE period_step : 1 avail_min : 144 period_event : 0 start_threshold : 576 stop_threshold : 576 silence_threshold: 0 silence_size : 0 boundary : 5188146770730811392 appl_ptr : 0 hw_ptr : 0 The same song converted to 48000 Hz plays without underruns with buffer size of 256 frames: Playing WAVE '/tmp/ksp48000.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Stereo Plug PCM: Hardware PCM card 0 'CA0106' device 0 subdevice 0 Its setup is: stream : PLAYBACK access : RW_INTERLEAVED format : S16_LE subformat : STD channels : 2 rate : 48000 exact rate : 48000 (48000/1) msbits : 16 buffer_size : 256 period_size : 64 period_time : 1333 tstamp_mode : NONE period_step : 1 avail_min : 64 period_event : 0 start_threshold : 256 stop_threshold : 256 silence_threshold: 0 silence_size : 0 boundary : 4611686018427387904 appl_ptr : 0 hw_ptr : 0 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1315212 Title: [CA0106 - CA0106, playback] Playback problem - Surround dies, no valid output To manage notifications about this bug go to: https://bugs.launchpad.net/alsa-driver/+bug/1315212/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
