19 Oct
2007
19 Oct
'07
7:44 p.m.
Hi group,
I think I have found a problem with the USB sound driver? It appears
that the current drive returns a x'81' for silence but it should be a
x'7f'.
When I use my laptop's sound device and record without a mic, I get
a file full of x'7f's. If I do the same with my cheap-o USB device
I get a file full of x'81's. The sound quality from the laptop is
unacceptable, so that is way I want to use the USB device.
I have written a recording program that I have a 'silence' filter
that filters out segments of dead air. It works with the laptop's
sound device but not the USB device. The filter works by remove
x'7f's after allowing a selectable amount. I get the results using
arecord which does not have the filtering.
The USB device is a C -Media Electronics, Inc. I am running FC6.
[root@laptop ~]# lsmod |grep snd
snd_usb_audio 81985 0
snd_usb_lib 21057 1 snd_usb_audio
snd_rawmidi 28481 1 snd_usb_lib
snd_hwdep 13637 1 snd_usb_audio
snd_ali5451 27853 1
snd_ac97_codec 99813 1 snd_ali5451
snd_ac97_bus 6593 1 snd_ac97_codec
snd_seq_dummy 8133 0
snd_seq_oss 37057 0
snd_seq_midi_event 11841 1 snd_seq_oss
snd_seq 57009 5 snd_seq_dummy,snd_seq_oss,snd_seq_midi_event
snd_seq_device 12365 4 snd_rawmidi,snd_seq_dummy,snd_seq_oss,snd_seq
snd_pcm_oss 46433 0
snd_mixer_oss 20545 1 snd_pcm_oss
snd_pcm 80965 4 snd_usb_audio,snd_ali5451,snd_ac97_codec,snd_pcm_oss
snd_timer 26693 2 snd_seq,snd_pcm
snd 58181 140
snd_usb_audio,snd_rawmidi,snd_hwdep,snd_ali5451,snd_ac97_codec,snd_seq_oss,snd_seq,snd_seq_device,snd_pcm_oss,snd_mixer_oss,snd_pcm,snd_timer
soundcore 12193 1 snd
snd_page_alloc 14281 1 snd_pcm
Where do I report this 'bug' or how do I fix it?
Thanks for your time. Sorry for the multiple posting, not sure where is
should have gone.
--
William Estrada
MrUmunhum(a)popdial.com
Mt-Umunhum-Wireless.net ( http://Mt-Umunhum-Wireless.net )
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