Audio/Video Out of Sync

[MacFH - C E Macfarlane]

> -----Original Message-----
> From: get_iplayer [mailto:get_iplayer-bounces at lists.infradead.org] On
> Behalf Of MacFH - C E Macfarlane
> Sent: 07 August 2016 16:22
> To: alan at soulman1949.com; get_iplayer at lists.infradead.org
> Subject: RE: Audio/Video Out of Sync
> 
> > -----Original Message-----
> > From: get_iplayer [mailto:get_iplayer-bounces at lists.infradead.org] On
> Behalf Of Alan Milewczyk
> > Sent: 07 August 2016 10:00
> > To: get_iplayer at lists.infradead.org
> > Subject: Re: Audio/Video Out of Sync
> >
>>> On 07/08/16 09:32, Jim web wrote:
>>>
>>> If there is a synch problem due to missing chunks at some point, does
>>> that persist or accumulate to the end of the file? i.e. if the synch
>>> is correct at the end, does that indicate that it was probably OK
>>> thoughout?
> 
> Dunno, I've been too busy to have yet watched any of the Proms I've
> downloaded this year.

I can now answer this, after a fashion.  In Saturday night's PVR download,
which I previously stated was without error and still unfinished, I spoke
too soon  -  there was the following error in the final download, which was
of 'Click':
	Recording:   176.55MB / 410.47MB   403kbps  43.0% 01:19:15 remaining
	Recording:   176.97MB / 410.47MB   403kbps  43.1% 01:19:07 remaining
	WARNING: Segment not found (64)
http://cp401489-vh.akamaihd.net/i/iplayerstream/secure_auth/,800kbps/modav/b
Unknown-f410c81d-5150-4e9b-a09d-
814896e567ea_b07ncgjn_1470417600045,1500kbps/modav/bUnknown-f410c81d-5150-4e
9b-a09d-814896e567ea_b07ncgjn_1470417600655,3200kbps/modav/bUnknown-f410c81d
-5150-4e9b-
a09d-814896e567ea_b07ncgjn_1470417598703,.mp4.csmil/segment64_2_av.ts
	WARNING: There may be a gap near 630 secs in programme
	Recording:   177.38MB / 410.47MB   402kbps  43.2% 01:19:07 remaining
	Recording:   177.79MB / 410.47MB   402kbps  43.3% 01:19:02 remaining
When I watched the programme, all hell broke loose at one point, presumably
the point of error.  The audio continued, but the video went completely and
could not be resync'ed at all, showing seemingly random frames from the
content each for a second or two before finding another to display.  To
restore normality, I had to restart  playback from just after the original
fault.

How much of this behaviour is governed by the codec, and how much by Window
Media Player 12, I can't be sure.