PasTim wrote: 
> I wonder if it's worth stepping back briefly and making sure what your
> system is, what works and what doesn't.  This is just random imaginings,
> so please ignore if I'm off-beam.
> 
> As I understand it:
> 
> - your LMS is on a Windows VM in Microsoft's Azure Cloud, which reports
> that it is Dublin so is 'non-UK'
> - you can use squeezelite locally in the UK (I assume) to some local
> audio device and that works in all cases - squeezelite supports aac
> natively
> - you have some other SB devices (sorry I forget which), again in the
> UK, which are older - they do not support aac natively and so faad is
> used to transcode
> - on the latter devices, all on demand streams work (including using
> faad), but live plays for a few seconds and then stops
> - prior to the new plugins (and hence prior to HLS and the BBC's new
> non-UK rules) it all worked OK
> 
> So what's different between the iPlayer Plugin Live and On Demand, given
> that everything else is much the same, including the use of HLS, aac and
> faad?  Well one thing is that the live service is location dependent.
> 
> When I initially tried to use MySqueezebox.com direct to my Touch Radio
> in the UK I couldn't get it to work because it was deemed to be a
> foreign source.  Before I was told a possible fix for this (adding
> #noslim=1 to the URLs) I seem to recall I got a short burst of sound and
> then nothing, as if I was being cut off (but note that this may be a
> false memory - I have several such!).  
> 
> Nonetheless yours is, as far as I know, the only reported case of this
> behaviour, so I wonder if something about the cloud-based nature of your
> system is upsetting the CDNs/BBC and causing them to cut you off.  Could
> there be some confusion about IP locations between the cloud and your
> local systems?  Is everything being reported to the CDNs/BBC coming from
> a Dublin IP, or is there a mix including your UK IP address?  Could
> squeezelite be working because it isn't doing something that your
> players are doing?
> 
> Random thoughts - sorry :)

Good theory, but I think the evidence from the log is that the data
isn't being cut off - the first 32 seconds of stream data has definitely
been received in the plugin, but only the first 3 seconds or so is
played before the rest is lost somewhere in the transcode system.

On windows in particular the transcode processing looks pretty
complicated - the data is streamed via a socket into a program called
socketwrapper, which then pipes the stream in pieces into and out of the
faad and flac programs, before the transcoded stream is finally being
sent to the player. I think it is highly likely that is where the
problem lies, and that it results from running this all on a cloud
server (non-uk may be a factor) which has significantly different
operating characteristics to those anyone has encountered on a home
windows machine. For example the networking looks to be extremely fast
(not unexpected - a cloud server must have a good internet connection) -
fetching and pushing the first 32 seconds of audio into the
socketwrapper in under a second. On the other hand, I'd expect that
running in a VM on a machine shared with perhaps many other users, the
time to task switch between all the processes involved in transcoding
might be a bit slow. A total guess, but it could be a buffer problem in
socket wrapper that would never be encountered in a normal home windows
machine.

The thing is, even if we go to the trouble of trying to diagnose this
problem, it is quite likely that we'll end up in the same situation as
for the fix we put into faad.exe - something will need changing in a
long-standing and well proven bit of code, and there will be a lot of
resistance to updating the distribution - especially as there is now
only one user reporting the problem. We could, of course, learn
something important in the process and end up fixing something that is
actually affecting a lot more folk, in a more intermittent way. So it
may be worth spending some more time trying to look at this - I just
don't have time myself at the moment.

It's a bit of a cop out, but I also get the impression that you are UK
based psketch - is that so? I can understand why you have chosen to run
LMS on a cloud server, but if you are in the UK could you not just set
up a raspberry pi as a local LMS server just for BBC radio? The B+ is
only £20 on amazon, plug it straight in the router - job done! Then
you'd also get the benefit of the high bit-rate streams, with just the
minor hassle of switching players to and fro between servers.


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