Re: [Jack-Devel] Capture problems with jack2 on Axia-Alsa device

Hi everyone, capturing from ALSA capture devices via the Jack2 sound server (1.9.12), results in too high pitched wav files (they are playing "too fast" and sound like the "chipmunks"). If I run the same capture directly from the ALSA devices (without Jack involved), everything sounds as expected without any problems. Audio examples: Capture via jackrec: https://filebin.ca/3pyMxBw8cexQ/test-jackrec.wav Capture via arecord: https://filebin.ca/3pyOPjcKGym5/test-arecord.wav The device in question is a "virtual" Axia-ALSA (Livewire+) audio device on CentOS 7 which operates at a sample rate of 48kHz and a bit depth of either 16 or 32. As far as I can see, the sample rate and format detection on the Jack side looks correct. I'm therefore looking for some guidance on how to further debug this, I most certainly missed something obvious. I've also tried to play an mp3 file via mpg123 over jack (without the involvement of the Alsa device) and record it again with jackrec. This works and sounds correct. Here is what I've tried and what the environment looks like: # Capabilities of the Axia-ALSA device arecord -D hw:0 --dump-hw-params Recording WAVE 'stdin' : Unsigned 8 bit, Rate 8000 Hz, Mono HW Params of device "hw:0": -------------------- ACCESS: MMAP_INTERLEAVED RW_INTERLEAVED FORMAT: S16_LE S32_LE SUBFORMAT: STD SAMPLE_BITS: [16 32] FRAME_BITS: [16 256] CHANNELS: [1 8] RATE: 48000 PERIOD_TIME: (41 1365334) PERIOD_SIZE: [2 65536] PERIOD_BYTES: [64 131072] PERIODS: [1 1024] BUFFER_TIME: (41 1365334) BUFFER_SIZE: [2 65536] BUFFER_BYTES: [64 131072] TICK_TIME: ALL -------------------- arecord: set_params:1299: Sample format non available Available formats: - S16_LE - S32_LE # Capture via arecord directly from the ALSA device (without jackd) # This works as expected and the WAV file sounds fine arecord -D hw:0 -c 2 -d 10 -r 48000 -f S32_LE -v /tmp/test-arecord.wav Recording WAVE '/tmp/test-arecord.wav' : Signed 32 bit Little Endian, Rate 48000 Hz, Stereo Hardware PCM card 0 'Axia' device 0 subdevice 0 Its setup is: stream : CAPTURE access : RW_INTERLEAVED format : S32_LE subformat : STD channels : 2 rate : 48000 exact rate : 48000 (48000/1) msbits : 32 buffer_size : 16384 period_size : 4096 period_time : 85333 tstamp_mode : NONE tstamp_type : MONOTONIC period_step : 1 avail_min

4096 period_event : 0 start_threshold : 1 stop_threshold : 16384 silence_threshold: 0 silence_size : 0 boundary : 4611686018427387904 appl_ptr : 0 hw_ptr : 0 # playing arecord wav (via my local notebook's HDA Intel PCH # device), sounds correct aplay test-arecord.wav Playing WAVE 'test-arecord.wav' : Signed 32 bit Little Endian, Rate 48000 Hz, Stereo # Starting jackd # Verbose output at: https://pastebin.com/YzHEGSnR jackd -d alsa -d hw:0 jackdmp 1.9.12 Copyright 2001-2005 Paul Davis and others. Copyright 2004-2016 Grame. Copyright 2016-2017 Filipe Coelho. jackdmp comes with ABSOLUTELY NO WARRANTY This is free software, and you are welcome to redistribute it under certain conditions; see the file COPYING for details no message buffer overruns no message buffer overruns no message buffer overruns JACK server starting in realtime mode with priority 20 self-connect-mode is "Don't restrict self connect requests" audio_reservation_init Acquire audio card Audio0 creating alsa driver ... hw:0|hw:0|1024|2|48000|0|0|nomon|swmeter|-|32bit configuring for 48000Hz, period = 1024 frames (21.3 ms), buffer = 2 periods ALSA: final selected sample format for capture: 32bit integer little-endian ALSA: use 2 periods for capture ALSA: final selected sample format for playback: 32bit integer little-endian ALSA: use 2 periods for playback # Capture via jackrec # This results in a too high pitched WAV file # Verbose output at: https://pastebin.com/PCnymKLA jackrec -f /tmp/test-jackrec.wav -d 10 -b 32 system:capture_1 system:capture_2 # playing jackrec wav (via my local notebook's HDA Intel PCH # device), sounds incorrect aplay test-jackrec.wav Playing WAVE 'test-jackrec.wav' : Signed 32 bit Little Endian, Rate 48000 Hz, Stereo System environment: Distribution: CentOS 7.4.1708 Kernel: 3.10.0-693.17.1.el7.x86_64 ALSA Utils: 1.1.3 Jackd: 1.9.12 The jackd was rebuilt from Fedora source RPM to be able to test with the latest version: https://build.opensuse.org/package/show/home:radiorabe:audio/jack-audio-c onnection-kit Many thanks and best regards Chris _______________________________________________ Jack-Devel mailing list Jack-Devel(a)lists.jackaudio.org http://lists.jackaudio.org/listinfo.cgi/jack-devel-jackaudio.org