Compilation output of chan_alsa: gcc -o chan_alsa.o -c chan_alsa.c -pthread -I/home/patrick/redhat/BUILD/asterisk-1.4.0/include -pipe -Wall -Wstrict-prototypes -Wmissing-prototypes -Wmissing-declarations -include /home/patrick/redhat/BUILD/asterisk-1.4.0/include/asterisk/autoconfig.h -march=i686 -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m32 -march=i386 -mtune=generic -fasynchronous-unwind-tables -fPIC -DAST_MODULE=\"chan_alsa\" chan_alsa.c: In function 'sound_thread': chan_alsa.c:331: warning: ignoring return value of 'read', declared with attribute warn_unused_result chan_alsa.c: In function 'alsa_call': chan_alsa.c:536: warning: ignoring return value of 'write', declared with attribute warn_unused_result chan_alsa.c: In function 'answer_sound': chan_alsa.c:549: warning: ignoring return value of 'write', declared with attribute warn_unused_result chan_alsa.c: In function 'alsa_hangup': chan_alsa.c:580: warning: ignoring return value of 'write', declared with attribute warn_unused_result chan_alsa.c: In function 'alsa_indicate': chan_alsa.c:772: warning: ignoring return value of 'write', declared with attribute warn_unused_result gcc -o chan_alsa.so -pthread -shared -Xlinker -x chan_alsa.o -lasound -lm -ldl $ rpm -qa | grep alsa alsa-lib-devel-1.0.13-1.fc6.i386 alsa-lib-1.0.13-1.fc6.i386 alsa-utils-1.0.13-1.fc6.i386 $ aplay -l **** List of PLAYBACK Hardware Devices **** card 0: IXP [ATI IXP], device 0: ATI IXP AC97 [ATI IXP AC97] Subdevices: 1/1 Subdevice #0: subdevice #0 card 1: Modem [ATI IXP Modem], device 0: ATI IXP MC97 [ATI IXP MC97] Subdevices: 1/1 Subdevice #0: subdevice #0 Output from configure --with-asound checking for snd_spcm_init in -lasound... yes checking alsa/asoundlib.h usability... yes checking alsa/asoundlib.h presence... yes checking for alsa/asoundlib.h... yes Playing a sound with aplay: $ aplay /usr/share/system-config-soundcard/sound-sample.wav Playing WAVE '/usr/share/system-config-soundcard/sound-sample.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo