[mythtv-users] frontend crash during UK dvb-t playback - only at adverts

[Alan Bates]

ok - bit more info. editing some of the setup options changed the
behaviour. disabling "extra audio buffering" in tv playback options
means the loss of audio does not occur at the commercial break. great!
but the reason it's enabled is because if it's not, playback loses
audio, crackles AND video ffwds at some points - seemingly random
although changing aspect ratio manually makes it happen. points to an
audio/buffer problem?

On 9/20/05, Alan Bates <bite.my.shiny.metal.ass at gmail.com> wrote:
> i'm running 0.18 - most recent one available for fc4. not certain
> which version of the nova-t i'm running - uses tda1004 firmware, so
> it's an oldish one i think. oddly, when i run the frontend from the
> terminal to check what it reports, the frontend seems less inclined to
> crash, but still has the audio problem - namely, sound drops out after
> the green frame and there's an occasional crackle until either it
> recovers itself or i skip forward then back.
>
> in the frontend terminal at the point where the problem occurs it
> reports: GetNextFreeFrame() - served a busy frame. Dropping
>
> followed by a few prebuffering pauses.
>
> i'll keep trying to kill it in terminal - if it remains more stable
> i'll just change my startup to run it that way.
>
> On 9/20/05, Stephen Williams <stephen.gw at gmail.com> wrote:
> > On 9/20/05, Alan Bates <bite.my.shiny.metal.ass at gmail.com> wrote:
> > > hi all – I now have a stable dvb-t myth setup running on an up-to-date
> > > fedora core system, using the hauppage nova-t. only major problem thus
> > > far is:
> > >
> > > watching certain UK channels, the frontend crashes when the commercial
> > > break begins – happens both with recordings and livetv. channels
> > > identified so far are channel4, e4/e4+1 and  abc1.
> > >
> > > I suspect the reason is that these channels broadcast in a variety of
> > > aspect ratios, and switch over at the start  of the adverts, causing a
> > > break in the signal of some kind – i.e. main broadcast  is in 16:9,
> > > channel ident may be in low-res 4:3, followed by ad in 16:9. this
> > > often causes a broken keyframe (?) which the system struggles to
> > > recover from, manifesting itself in a green frame, a period of
> > > scrambled or non-existent audio, and quite often, the complete and
> > > sudden death of the frontend. rest of the programme and other channels
> > > are fine.
> > >
> > > anyone else seeing  this behaviour or anything similar? let me know if
> > > there's any debug info that'd  help…
> >
> > I've been running 0.18 since it was released on DVB-T in the UK with a
> > (version 909) Nova-T. It's quite normal for the adverts and the actual
> > programme to be in different aspect ratios, at most I see the odd
> > green frame / short garbled video but very rarely.
> >
> > You don't say what version of Myth you're running. The current SVN
> > head is undergoing a major DVB re-write so i'd use the 0.18-fixes
> > branch for a production system until that all settles down.
> >
> > Have a look in the logs to see if there's anything useful, otherwise
> > try and get a backtrace (see the user guide for instructions).
> >
> > Steve
> >
>