Jaroslav, Thanks for your reply. I looked at the section of code you pointed to and wondered if you meant I should use snd_pcm_sw_params_stop_threshold() rather than start_threshold, as you suggested. I couldn't actually get snd_pcm_sw_params_get_boundary() to work since it wouldn't compile for me, but I tried various boundary values for the stop threshold. When doing this, I managed to eliminate the underruns. However, when my sample-writing routine is invoked by a late signal, then some strange noise creeps into my output audio and never goes away. I don't understand this since I am replenishing the buffer with new audio so I would expect the noise to go away as soon as it is overwritten.
Maybe I should ask the question in a more open-ended way. I have both incoming and outgoing audio and the two drift apart when I get playing underruns. Although it is not really the case, you could think of the outgoing audio as "echoing" the incoming audio. Why does this happen and what can I do about it? Thaks Very Much, Chris > > Put another way, I would like the driver to ignore underruns and simply > allow the start and end pointers to cross over one another. > > Is this possible (or clear)? Why not? Simply set start_threshold from sw_params to boundary wrapper value. The nice example code is in alsa-lib/src/pcm/pcm_direct.c - look for snd_pcm_sw_params_get_boundary() and lines around it. A side note: You might move the read pointer (capture) manually via the snd_pcm_forward() function to replace the garbage with silence or something better (in case of underrun of course) ------------------------------------------------------- This SF.net email is sponsored by: VM Ware With VMware you can run multiple operating systems on a single machine. WITHOUT REBOOTING! Mix Linux / Windows / Novell virtual machines at the same time. Free trial click here: http://www.vmware.com/wl/offer/345/0 _______________________________________________ Alsa-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/alsa-devel
