Radio 'chop' - how can I fix it?

[Clarkie]

I've just installed AlienBBC on my SS (v6.5) and it all seems to work pretty well when I run the AlienBBC streaming 'test' on my PC - the sound is constant and no breaks.

However, when I connect to the radio stream from the Squeezebox, it seems to play around 20 seconds of sound, and then 'chops' a few seconds out, and then sound again, then not. And so on..

I've pushed the 'cache' in the server settings to 30 seconds (the documented maximum) but that does not help

Any ideas out there?

[bpa]

Is you SB wired or wireless ?

If it is wireless then you may have a wireless problem. You should run a network test and see what speed you connection suppports. By default AlienBBC uses Flac to SB and this requires about 1500kbps

[Clarkie]

I'm running a wifi network @ 54Mbps from the room above the SB - NetStumbler is showing a huge network signal, and my laptop works at blinding speeds.

I'm not using any other devices on the network when this issue happens though, so it's not congestion

I have noticed, however, that the SB 'page' on the RHS of the SlimServer HTML page 'refreshes' approx every 20 secs. I haven't yet been able to establish a link between this 'page refresh' and the 'chop' on the radio signal - so it could be some sort of caching problem, I guess, that is related to the power of my desktop.

I must say that this only happens with the Radio - not with general music playing, which is completely stable and works just fine. So, I've assumed that there's some causal link between the streaming of data 'onto' my PC (SlimServer) and then pushing it back out onto the WLAN and out to the SqueezeBox. Ideas?

The PC spec is a number of years old - Intel Pentium 3 chipset (500Mhz, I think), 384Mb RAM and XP Pro loaded (so there's not much left for anything else). I haven't tried changing OS-level parameters for cache etc, just the SS settings. Anyone know of system variables that might help?

[bpa]

Please run the network test from the SB ? There may be other factors and at least with the network test we can be be clear about the state of the wifi network in relation to the SB.

The network is rated at 54Mbps but rarely do people get that throughput and the antenna in the SB is different to a laptop's which usually has 2 larger antennae.

Bowser Page refresh has nothing to do with radio chop.

[Clarkie]

Hi bpa. I've just run the network test from the SB, and it got up to 3000 kbps (all at 100%/100%), with 4000 kbps sitting between 89% and 92% and 5000 kbps sitting at 74% to 82%. These last 2 occasionally hit higher 'blips', but nothing worth counting. The % ranges I've given were fairly constant.

I get my MP3 music fine, at a constant rate.

Also, I timed the 'chop' today and it's around 2-4 seconds, not 20. I apologise, I was getting mixed up somehow, and my memory was not accurately recalling the facts.

I'm reading through the other forums again - this 'chop' seems to be a common issue - but anything you can suggest would be very welcome

[bpa]

The 3000 should be enough to serve Flac. However you could try sending the BBC stream in MP3 and not Flac. To do this
1. Install lame.exe if you have not got it installed already. Use version 3.96.1 It's available form many sites but this site used to be OK http://www.free-codecs.com/download/Lame_Encoder.htm
make sure you have an Antivirus check installed just in case. Install lame.exe into the same directory as mplayer.exe on your PC (it will be in slimserver Bin/MSWin something)

2. Restart slimserver - if SS can "see" lame then under server setting/Filetypes - you will be able to check the RTSP->MP3 box and uncheck the RTSP->WAV and RTSP->FLAC boxes.

Now try playing a BBC stream.

As examples that there could be other causes - I've found in one case a faulty server network card (even though the user happily browsed and downloaded files) and another with a network driver that needed to be updated as mplayer is very exacting on the network driver.