The .asoundrc I posted split the 4 inputs of the Delta 44 into 2 recording pairs. It worked with arecord but it would not work with the app that I wanted to use it with :( I had the same errors that you have reported. Using jack and the alsa jack plugin... http://jackaudio.org/faq/routing_alsa.html ...splits the pairs reliably, so I used that instead. Although I have the app source I do not know enough about alsa or the code to troubleshoot this further. By the way, splitting the 4 outputs into 2 playback pairs with dshare was not a problem. Although jack introduces some additional latency it was acceptable with in this case. zcx On 28/04/17 08:28, SREEKANTH SREEKUMAR wrote: > I have M-Audio M-Track Eight, a USB based soundcard that I use to play and record audio files using a python based tool I wrote. . . . > But, with the above, I figured out that it is not possible to play and record on multiple channels simultaneously. . . . > "ALSA lib pcm_dsnoop.c:606:(snd_pcm_dsnoop_open) unable to open slave > > arecord: main:722: audio open error: Device or resource busy" > . . . > > The user in the first post seems to have solved by adding the following to his .asoundrc: > > > pcm.D44_cslave { > type dsnoop > ipc_key 223456 > slave { > pcm "hw:0,0" > rate 48000 > period_time 0 # in microseconds > buffer_size 256 # in bytes > period_size 64 # in bytes > channels 4 > format S32_LE > } > bindings { > 0 0 > 1 1 > 2 2 > 3 3 > } > } > > pcm.D44_ch12_capture { > type plug > ttable.0.0 1 > ttable.1.1 1 > slave.pcm D44_cslave > } > > pcm.D44_ch34_capture { > type plug > ttable.0.2 1 > ttable.1.3 1 > slave.pcm D44_cslave > } . . . > Now, my questions are : > 1. What could be the right configuration for me if I want to use the input and output channels exclusively for capture/record and playing respectively? Also, are my `arecord` and `aplay` commands fine? > 2. If the error shows that dsnoop is indeed busy, then why was it not being shown in the output of `lsof /dev/snd/pcm*`. The error clearly says there is a definite problem with `dsnoop`, does that mean that it is not meant for simultaneous/multi-channel recording? I mean is there a conflict between `dsnoop` and `dshare` or if multiple instances of `dsnoop` is what is causing the problem? ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
