If this has been already tackled, sorry for the duplicate. I listen to the radio via my laptop when at home and pc when at work. Sometimes the feed cuts out, annoyingly so, and I have to reload the page to get it going again.
But sometimes it stops, mid-song, for a few seconds and then starts at exactly the same point. This has led me to wonder; is the ensuing feed delayed, was it going too fast before the delay, is it going faster to ‘catch up’ (doesn’t sound faster) or is it a hole in the space time continuum?
If the feed is delayed but going at the same speed, where is the bottleneck? Why does it only happen sometimes, is it too much ‘traffic’ at certain points of the day - bearing in mind the radio is coming from the BBC and is so almost 6,500 km away. Or is it? Does the BBC have servers in other locations where the feed will come from?
That last one sounds like a dumb question but maybe it isn’t. I realize the internets are ‘stored’ in various locations around the globe, but I’m guessing a live feed works differently.
Lots of questions, and a somewhat complicated answer…
The radio transmission you receive is a sequenced, digitized representation of the audio, with a set playback speed. It’s a bunch of bytes, which something on your device knows how to turn back into sound at a set playback rate. What you experience is an interruption in the delivery of that set of that digital data. After the interruption, it doesn’t go any faster to “catch up,” except that, as you noted, sometimes you can reset, and reacquire the feed.
So, for instance, if you’ve been listening to a transmission that has experienced several interruptions, and then start fresh listening to it on another device, what you hear on the new device might be in advance of the oft interrupted feed.
And to be technically correct, I’ll note that an audio playback decoder could compress the audio to catch up. I doubt any decoder encountered by a typical end-user does, though.
This can be a hard question to answer even for the guys who are charged with maintaining the transmission network. As an end-user, it’s usually “who knows?”
Maybe. Delays can be caused by load, but they can also be caused by a host of other things: routine maintenance, unexpected equipment failure, routing problems, just a myriad of things.
I don’t know about the Beeb’s radio distribution particulars, but a lot of media providers use what are known as content distribution networks, which basically use a dedicated network to distribute the feed to set of more local servers for eventual distribution to end consumers. This can be done for a number of reasons: Primarily, it’s because if there are a thousand listeners in South Africa, for instance, it’s more efficient to distribute one copy of the data to a server in Africa for local consumers to access than to distribute a thousand copies of the same thing to individual users straight from London. Sometimes it’s done to permit the insertion of local advertising.
Yes and no. In the end, whether it’s a decades-old file that you’re downloading, or the most recent broadcast from BBC, the underlying network is just getting you a set of digital data. But for live data, the provider may have taken steps to ensure that it’s transmitted more efficiently or quickly to you. He’s using the same networking functionality that is available to everyone, but he can choose to use it differently, or to use private networks or even other means to achieve an advantage.
Just to add, it’s not just a delay in the network that can cause a stream to pause. It can be something running on your computer. A background virus scan, a file backup, a software update, and a lot of other background tasks can start up and load the CPU or disk and cause a momentary pause in the playback software.
I listen to the radio via my TV all day (terrestrial signal - not cable). If I go upstairs and the radio is on up there, it is several seconds ahead of the TV. This is not buffering and it is always present and consistent.