[mythtv-users] black screen during playback

[Joey Morris]

Kenni Lund <kenni at kelu.dk> wrote on Sat, Jan 26, 2013 at 05:59:14PM +0100:
> 2013/1/26 Joey Morris <rjmorris.list at gmail.com>:
> > Kenni Lund <kenni at kelu.dk> wrote on Sat, Jan 26, 2013 at 11:03:51AM +0100:
> >> 2013/1/25 Joey Morris <rjmorris.list at gmail.com>:
> >> > I tried everything I could think of to isolate the problem:
> >> > systematically swapping out every piece of hardware in the system,
> >> > reinstalling the OS, upgrading Myth to 0.26, and deleting the playback
> >> > profiles so Myth would regenerate the default ones. I still had the
> >> > problem of the black screen during video playback using VDPAU. Nothing
> >> > in the logs pointed to a problem.
> >> >
> >> > Finally it occurred to me that a common denominator between all these
> >> > configurations was the hostname, which Myth uses to pull in settings
> >> > from the database. I gave the system a new hostname, and my video with
> >> > VDPAU returned! I have no idea which setting in the database was
> >> > causing the problem.
> >> >
> >> > The lesson for me in this exercise was that to get a truly clean slate
> >> > with a Mythfrontend re-install, you have to use a new hostname.
> >> > Otherwise you'll pick up all the settings from your previous install.
> >>
> >> I had that issue back in MythTV 0.24:
> >> http://www.mythtv.org/pipermail/mythtv-users/2011-July/318731.html
> >
> > I was also on 0.24 when my problem started. I read your thread at the
> > time along with a few others mentioning the same problem, but none of
> > them included a solution. Or if they did, the solution didn't work in
> > my case.
> >
> >> I came to the same conclusion as you - Changing the frontend hostname
> >> and hence getting a clean set of settings, fixed the issue. However,
> >> in my case the issue reoccurred some weeks after I reinstalled the
> >> system and changed the hostname. I did some further digging and I
> >> think I identified a VDPAU filter to be the cause of the issue or at
> >> least to be related to the issue. As far as I remember, my VDPAU
> >> filter were set to "vdpaucolorspace=auto". Once I deleted the string
> >> the issue got fixed (I didn't change the hostname / reset the
> >> settings, I only deleted that string) - and since I haven't seen the
> >> issue since, it seems like the issue somehow was related to that VDPAU
> >> filter.
> >
> > I don't think the VDPAU filter was the culprit in my case. Both the
> > working config and non-working config have the VDPAU filter set to
> > "vdpaucolorspace=auto".
> 
> So did mine, that's *exactly* the same situation as I had. Two
> frontends both with the default VDPAU filter enabled,
> "vdpaucolorspace=auto". One of the frontends suddently stopped working
> (black screen with audio under playback) with no changes to software
> or hardware. Once I changed the hostname to reset the settings, the
> frontend worked for at least some days up to a couple of weeks, after
> which the issue appeared again and I could change the hostname once
> again to temporarily "fix" the issue. After I had done this a number
> of times over a period of 3-4 months with no luck in identifying the
> real issue, I tried to pinpoint if I could avoid triggering the issue
> by using some other playback settings in MythTV.
> 
> While being on a non-working frontend, I was able to recover VDPAU
> playback functionality by removing "vdpaucolorspace=auto" *WITHOUT*
> changing the hostname or by doing any other changes to settings. At
> the same time, the black-screen issue did not reappear any more.
> 
> In other words, my conclusion was that removing "vdpaucolorspace=auto"
> fixed the black screen issue immediately and also avoided that the
> issue reappeared after some days/weeks.
> 
> If you experience the issue again in a couple of days/weeks, don't
> reset the settings, just try to delete the VDPAU filter and see if it
> doesn't fix the issue.

Thanks for the clarification. Yes, I'll be sure to give that a try if
the problem happens again and report the result here.