[icecast] Low frequency feedback?

[gtgbr at gmx.net]

Devin Campbell wrote:
> >> http://www.starbeamllc.com/images/feedback.mp3
> I guess my next question is:  is there something special about my stream
> or my songs that's causing this?  I'll have to do some experimentation.

Owtch, my ears. :( I find that 16 kHz beep most irritating, it hurts
even at low volumes. ;P

Anyways, the humming you hear is actually multiple tones, that spread
out in ripples - same like the 16 kHz (16050 Hz, to be exact) beep. The
interesting part is the frequencies of the ripples.

These are, in decreasing strength, 147 Hz, 440 Hz, 732 Hz, 1025 Hz, 1318
Hz. Those are the notes D, A, F#, C, E (and quite more, but those are
the ones that are visible in the analysis even with the "background"
music playing). This looks like some fucked up test tones generated by a
music/notes-aware progam. You say the 16 kHz thing is coming from
Cakewalk? Then the low hum is probably coming from there, too.

Why all this is happening, I don't know. However, both hum and beep look
so much alike, so an uneducated conclusion is that they're somehow
related. ;P

Maybe the attached pic helps you to find the culprit.

<p>Moritz
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