[mythtv-users] Problems with new setup

[HP-mini]

On Sun, 2013-09-08 at 17:50 -0400, Nicholas Fasano wrote:
> Please help. I'm a longtime mythtv user (running mythtv for about 10
> years now) and I have now run into a problem with a new installation
> of mythtv. I just moved to a new house with Comcast service, and have
> decided to build an entirely new mythtv backend/frontend from scratch.
> I have an HD Homerun Prime with a functioning cable card (I can watch
> it just fine on my iPad). I run mythbuntu packages that I have just
> installed and had the basics up and running just fine for about a day.
> As of today, however, I have been experiencing a strange set of errors
> on certain channels (and on every channel if given a long enough
> period of time). For example, when I tune a certain channel the video
> freezes within a second or two and I see many log entries as follows:
> 
> 
> $ mythfrontend.real
> 2013-09-07 23:40:40.480565 W  ThemeInfo: Unable to open themeinfo.xml
> for /usr/share/mythtv/themes/BlackCurves-OSD/themeinfo.xml
> 

<snip>
> 2013-09-07 23:42:54.509115 I  AOBase: Opening audio device
> 'front:CARD=PCH,DEV=0' ch 2(6) sr 48000 sf signed 32 bit reenc 0
> 
> 2013-09-07 23:42:54.510795 E  ALSA: Requested 500000us got 170666 buffer time
> 
> 2013-09-07 23:42:54.510875 E  ALSA: Try to manually increase audio
> buffer with: echo 192 | sudo tee
> /proc/asound/card0/pcm0p/sub0/prealloc
> 
> 2013-09-07 23:42:54.517661 E  ALSA: no playback control PCM found on
> mixer device default
> 
> 2013-09-07 23:42:54.517671 E  ALSA: Unable to open audio mixer. Volume
> control disabled
> 
> 2013-09-07 23:42:54.682352 I  VDPAU: Added 2 output surfaces (total 4, max 4)
> 
> 2013-09-07 23:42:58.687673 N  Player(0): Waited 102ms for video
> buffers AAAAAAAAAAALff
> 
> 2013-09-07 23:42:58.696080 I
> RingBuf(/livetv/1824_20130908034253.mpg): Waited 0.2 seconds for data

> 
> 2013-09-07 23:43:09.760865 E
> RingBuf(/livetv/1824_20130908034253.mpg): Took more than 10 seconds to
> be allowed to read, aborting.
> 
> 2013-09-07 23:43:09.764449 E  decoding error
> 
> eno: Unknown error 541478725 (541478725)
> 
> 2013-09-07 23:43:09.768301 E  decoding error
> 
> eno: Unknown error 541478725 (541478725)
> 
> 2013-09-07 23:43:09.773523 E  decoding error
> 
> 
> It continues with the decoding error forever. Any ideas? I'm thinking
> some sort of corrupt driver or possibly a hardware problem. I've
> updated nvidia drivers, swapped out RAM, and upgraded to 0.27 (as you
> can see above). I haven't been able to swap out the graphics card yet,
> but that's on the list. If that doesn't work, I'm going to reinstall
> Ubuntu.
> 
> 
> Any ideas would be greatly appreciated.
> 
Maybe the recent MHEG interactiveTV bug in the RC1 ? There are posts
here about it..

Test your nVidia driver/VDPAU outside of MythTV.

You might get rid of some the other warnings by:
- check theme updates in theme chooser (FE/setup)
- rescan audio devices (FE/setup)

The internal volume control only works with PCM output to dmix or
re-encoding (AC3).

The only soln (I know) to fix the alsa buffer warning/error is to change
the ownership/permissions of /proc/asound/card0/pcm0p/sub0/prealloc to
allow audio group to write.