Icecast Streaming Media Server

[Anonymous]

We've been using icecast several months now to stream our LPFM station, WXBH-LP (http://wxbh.org:8000/stream.ogg).

Today I noticed that our sound quality suddenly changed from very good (at 128kbs) to a sound that can best be described as "tinny".

I expected the problem to be in the signal we were uploading but was surprised that I was able to correct the problem by simply restarting icecast.

Is this a known problem? What triggers it?

Any help would be appreciated.

Thanks in advance.

John Hicks
WXBH-LP, Louisville
wxbh.org

[karlH]

icecast does not change the encoding of the audio signal for any codec. If there is a change then it has to be something either in the encoder or possibly the player.

An example of a change in the encoder could be down to a samplerate change, which is something that icecast can handle but many players cannot. Without knowing the specifics of the encoder, the material and the player before and after the change you noticed then I can only guess.

Not that in restarting icecast, you dropped the connection from the player and the source client so they both would have to reconnect and the difference (assuming something like samplerate) would of been rectified.

karl.

[Anonymous]

Yes, I was surprised that restarting Icecast solved the problem since I thought that (as you confirm) Icecast doesn't change the encoding. (But restarting Icecast seemed like a simplest first step in ruling out all the causes.)

We are using Darkice as our encoder and it is encoding at a constant 128kbps rate from a line-in input. I could monitor the quality of the signal going in to the sound card and it was fine

If this happens again, I'll try restarting Darkice to see if that corrects the problem also.

It's still curious, assuming the culprit is Darkice, that having it reconnect solved the problem.

(Thanks for your prompt response.)[/quote]

[karlH]

It can be the capture part of the dsp, I've have setups where after a period of time, the audio signal became distorted just because of timing of the reads in the source client (clock sync drift). Darkice may not have that problem but I don't know that application well enough.

karl.