[mythtv-users] remote MythTV system has suddenly lost sound

[Michael T. Dean]

Mark Knecht wrote:

>Hi,
>   I run a remote setup for my parents. It's worked very well for
>about 6 months. Very few problems. However a couple of days ago my dad
>called, told me there was a power outage and wanted to shut the
>machines down before the UPS's ran out of juice. We shut them down by
>hand even though the APC ups daemon probably would have done it
>anyway.
>
>   Since bringing the system up he has had no sound for the last two
>days. Video seems to be working fine.
>
>   The backend machine itself is still recording, and alsa is working
>on that system. Remotely I can do aplay FILE.wav and my dad reports
>that he hears sound, so the failure is not a total sound failure.
>
>   I checked that mythfrontend says it's using /dev/dsp, and that
>/dev/dsp does exist:
>
>mark at gandalf ~ $ ls -la /dev/dsp
>lrwxrwxrwx  1 root root 9 Nov 18 07:13 /dev/dsp -> sound/dsp
>mark at gandalf ~ $
>
>   How can I get more info on what is going wrong?
>
>   I rebooted the system earlier this morning. I'm getting these
>troubling messages in the mythbackend.log file:
>
>Starting up as the master server.
>2005-11-18 07:13:54.659 New DB connection, total: 2
>2005-11-18 07:13:54.706 Channel(/dev/v4l/video0)::Open(): Can't open
>video device, error "No such file or directory"
>2005-11-18 07:13:54.760 Channel(/dev/v4l/video0)::Open(): Can't open
>video device, error "No such file or directory"
>2005-11-18 07:13:54.761 ChannelBase: Could not find input: Tuner 0 on
>card when setting channel 4
>
>2005-11-18 07:13:54.766 New DB scheduler connection
>2005-11-18 07:13:54.776 New DB connection, total: 3
>2005-11-18 07:13:54.784 mythbackend version: 0.18.1.20050510-1 www.mythtv.org
>2005-11-18 07:13:54.841 Enabled verbose msgs :important
>2005-11-18 07:14:02.391 Seem to be woken up by USER
>2005-11-18 09:40:42.939 adding: gandalf as a client (events: 0)
>2005-11-18 09:40:51.522 adding: gandalf as a client (events: 1)
>
>
>However /dev/v4l/video0 does exist:
>
>gandalf ~ # ls -al /dev/v4l/video
>video0   video24  video32
>  
>
Heh.  You've lost your "-l".  ;)

>gandalf ~ # ls -al /dev/v4l/video0
>crw-rw----  1 root video 81, 0 Nov 18 07:13 /dev/v4l/video0
>gandalf ~ #
>  
>
Is the user running mythbackend in the video group?  Is the user running 
mythfrontend in the (probably) audio group?

Perhaps group settings got changed before the reboot.  Since Myth was 
already running in a process with previous group settings, they didn't 
cause problems.  However, when rebooting, Myth got a new process--with 
the new group settings...

Mike