Updates to F13 Bollix VLF Monitoring (audio)

[Chuck Forsberg WA7KGX N2469R]

  Previously I reported on audio issues with Fedora updates
affecting the VLF monitoring at omen.com.

Unfortunately, recent updates have really messed things up,
to the point I may have to consider using a different distro.

For quite some time I have been using an Asus pcie audio
card for monitoring VLF signals.  The computer also has
the motherboard audio.  During upgrades and/or reboots
Fedora would arbitrarily swap the two devices, but I was
able to correct the problem by rebooting again or changing
the device in Gnuradio.

A recent upgrade changed something and I was no longer
able to access the Asus card.  I disabled the motherboard
audio and VLF monitoring was back in business.  But then
the audio input would spontaneously mute itself every
few hours or so.  The sound applet shows the input unmuted,
but I had to mute and unmute  the input audio to get it working.

So I added
amixer -c 0 sset Line,0 100%,100% unmute cap >/dev/null  2>/dev/null
every minute via crontab.  This keeps the line from going dead,
but now the gain or something randomly changes from
time to time.  You can see the result at omen.com/vlf12.php

I know Linux audio is a mess but an unstable mess is worse.

-- 
Chuck Forsberg WA7KGX N2469R     caf at omen.com   www.omen.com
Developer of Industrial ZMODEM(Tm) for Embedded Applications
   Omen Technology Inc      "The High Reliability Software"
10255 NW Old Cornelius Pass Portland OR 97231   503-614-0430