I would first remove the audio source then short the inputs to the soundcard, run it overnight, and see if the spikes appear. That would determine if the spikes are in the source itself or somehow created in the PC. Most people don't do automatic updates on their linux boxes, but by chance do you have your update set for 2:30AM? Is that scanner (radio) audio? -----Original Message----- From: Peter Hoffmann <ph@xxxxxxxxxxxxxxxxxx> Date: Fri, 20 May 2011 16:44:39 To: <alsa-user@xxxxxxxxxxxxxxxxxxxxx> Subject: Spikes when recording Hello, I'm recording audio 24/7 with a delta 1010 sound card and have a strange problem: Every night at 2:30 I get spikes and some inaccurancy within some seconds in a one hour length recording. I've upload a screenshot to illustrate the problem: http://img88.imageshack.us/img88/4562/spikesh.png My .asoundrc pcm.capt { type dsnoop ipc_key 223456 slave { pcm "hw:0,0" rate 8000 period_time 0 period_size 320 channels 12 format S32_LE } } pcm.c1 { type plug ttable.0.0 1 slave.pcm capt } pcm.c2 { type plug ttable.0.1 1 slave.pcm capt } pcm.c3 { type plug ttable.0.2 1 slave.pcm capt } pcm.c4 { type plug ttable.0.3 1 slave.pcm capt } pcm.c5 { type plug ttable.0.4 1 slave.pcm capt } pcm.c6 { type plug ttable.0.5 1 slave.pcm capt } pcm.c7 { type plug ttable.0.6 1 slave.pcm capt } pcm.c8 { type plug ttable.0.7 1 slave.pcm capt } I'm recording with arecord -q -f cd -t wav -d 3600 -c 1 -D c1 out.wav. Any hints where the problem might be? Kind Regards, Peter Hoffmann ------------------------------------------------------------------------------ What Every C/C++ and Fortran developer Should Know! Read this article and learn how Intel has extended the reach of its next-generation tools to help Windows* and Linux* C/C++ and Fortran developers boost performance applications - including clusters. http://p.sf.net/sfu/intel-dev2devmay _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user ------------------------------------------------------------------------------ What Every C/C++ and Fortran developer Should Know! Read this article and learn how Intel has extended the reach of its next-generation tools to help Windows* and Linux* C/C++ and Fortran developers boost performance applications - including clusters. http://p.sf.net/sfu/intel-dev2devmay _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
