Hi; My level of sound knowledge is pre-newbie. Never played with sound adjustments before and only own one cd recording. But ... My main specific problem is that I can't get some apps to use PCM. tvtimes keeps reverting to line-in Audacity gives error: "There was an error initializing the audio i/o layer. ..." Every time I logon, PCM gets muted in my mixer gui. On 'line-in' my speakers hiss and squawk and the event sounds are terrible but I have no background noise problems when 'line-in' is muted and PCM is open. CD's play fine. My tvtimes configuration file /etc/tvtime/tvtime.xml is set to <option name="MixerDevice" value="/dev/mixer:pcm"/> gstreamer-properties gui (Multimedia Systems Selector) test gives me the following: With PCM on and 'line-in ' muted: Output ALSA pipeline alsasink = good clear sound. Input ALSA pipeline alsasrc = no sound (crashes gui) With PCM muted and 'line-in ' on: Output ALSA pipeline alsasink = sound + hissing background. Input ALSA pipeline alsasrc = no sound (crashes gui) permissions on /dev/dsp /dev/audio /dev/mixer all crw------- dmesg says at the audio portion of startup bttv is being installed. The literature I have read says that it should be alsasound. Similarly, init.d does not contain alsasound as it is supposed to. I have just clean installed Fedora Core 4 . Under FC3 I didn't have a memorable sound problem, but, then I wasn't looking. Fedora Core 4 is supposed to have ALSA as part of the Kernal. I am using P4 on a Intel 82850 motherboard, Ensoniq 5889 AudioPCI sound card and an ATI TV Wonder tuner. Also listed is Brooktree Bt878 video capture and Bt878 audio capture. I ran lsmod | grep ^snd and got the following: snd_ens1371 31649 1 snd_rawmidi 30305 1 snd_ens1371 snd_ac97_codec 75961 1 snd_ens1371 snd_seq_dummy 3653 0 snd_seq_oss 37057 0 snd_seq_midi_event 9153 1 snd_seq_oss snd_seq 62289 5 snd_seq_dummy,snd_seq_oss,snd_seq_midi_event snd_seq_device 8781 4 snd_rawmidi,snd_seq_dummy,snd_seq_oss,snd_seq snd_pcm_oss 51185 0 snd_mixer_oss 17857 1 snd_pcm_oss snd_pcm 100169 3 snd_ens1371,snd_ac97_codec,snd_pcm_oss snd_timer 33605 2 snd_seq,snd_pcm snd 57157 12 snd_ens1371,snd_rawmidi,snd_ac97_codec,snd_seq_oss ,snd_seq,snd_seq_device,snd_pcm_oss,snd_mixer_oss, snd_pcm,snd_timer snd_page_alloc 9669 1 snd_pcm plus; soundcore 10913 1 snd plus; bt878 10457 0 tuner 27121 0 bttv 161393 1 bt878 video_buf 23749 1 bttv i2c_algo_bit 9289 1 bttv v4l2_common 5825 1 bttv btcx_risc 4937 1 bttv tveeprom 13017 1 bttv videodev 9537 1 bttv and; /dev/dsp I have moved my sound and TV cards to new slots and securely reset all my speaker leads. My Windows XP setup works perfectly with the following settings: WindowsXP Vol Control: 40% Wave: 40% SW Synth: 95% Line-in: Mute CD Audio: 50% I have played around with my mixer settings so often I no longer remember the original installed settings. I am flumexed. I have googled for three days now. Nothing seems simple enough for me to understand. TLDP How To's seem out of date. ALSA site has material that was published in 1999 and is largely irrelevant to my problems. No where is there a clean simple explanation of what the various mixer choices are for or what the various modules do. So besides an answer to the specific question above. Where can I get started leaning about using (really basic) sound? Regrds Bill