Audio/Video Out of Sync

[MacFH - C E Macfarlane]

Please see below ...

> -----Original Message-----
> From: get_iplayer [mailto:get_iplayer-bounces at lists.infradead.org] On
> Behalf Of Vangelis forthnet
> Sent: 10 August 2016 11:09
> To: get_iplayer at lists.infradead.org
> Subject: Re: Audio/Video Out of Sync
> 
> On Wed Aug 10 09:53:51 BST 2016, Jim web wrote:
> 
> > However it might matter which server we access.
> 
> ... Well, of course it matters, a heck of a deal!
> 
> > Has anyone compared them to see
> > if one gives blips/premature ends when the
> > other(s) are OK?
> 
> I assume we are discussing here the "Segment not found"
> issue plaguing the hls tvmodes (and not the audio artifacts described as
> "blips" by C E Macfarlane in audio downloads, earlier in the thread...).

Yes, although I didn't think so at the time, after further investigation
this now appears to be a different issue  -  except that we should bear in
mind that a possible connection between the two might be that overloading of
the server(s) during the Olympics is causing both types of problem.

> One other thing; according to the commit comment at:
> 
> https://github.com/get-iplayer/get_iplayer/commit/48150e5
> 
> > HLS stream corruption has spread to radio
> 
> it would appear that radio downloads (hls radiomodes) are also affected; I
> haven't noticed such a report in the list/forum about "Segments not found"
> during audio downloads, possibly because the default radiomode (320k in
> the UK) uses MPEG-DASH streams.
> The hls radiomodes are hosted/streamed again on a unique Akamai CDN,
> whose hostname is:
> 
> "cp401492-vh.akamaihd.net"
> 
> again being (supplier="akamai_hls_open")
 
This is from last night's log, note that it's DASH:

Recording:    52.45MB / 343.28MB  1051kbps  15.3% 00:37:47 remaining
Recording:    52.79MB / 343.28MB  1050kbps  15.4% 00:37:47 remaining
ERROR: Failed to download segment (217)
http://aod-dash-uk-live.bbcfmt.vo.llnwd.net/usp/auth/vod/piff_abr_full_audio
/68539c-b07mwnpv/vf_b07mwnpv_1254dc58-2774-4be3-abbe-a9c9a16ecfbf.ism/dash/v
f_b07mwnpv_1254dc58-2774-4be3-abbe-a9c9a16ecfbf-audio=320000-217.m4s?s=14707
64708&e=1470807908&h=7e74c250e5a6188f182423550100df94
INFO: Recorded: 52.81MB in 00:08:12 at   879kbps to
/i-data/3fa24fb4/Data/Media/Downloads/Afternoon On 3 - Prom 24 Ginastera
Britten And Schubert.partial.m4a.m4a
WARNING: Retry recording for 'Afternoon on 3: Proms 2016 Repeats - Prom 24:
Ginastera, Britten and Schubert (b07mwnqs)'
INFO: File name prefix = Afternoon On 3 - Prom 24 Ginastera Britten And
Schubert                 
INFO: Resume recording file: /i-data/3fa24fb4/Data/Media/Downloads/Afternoon
On 3 - Prom 24 Ginastera Britten And Schubert.partial.m4a.m4a
Recording:    52.81MB / 343.28MB   807kbps  15.4% 00:49:08 remaining
Recording:    53.16MB / 343.28MB   809kbps  15.5% 00:48:56 remaining