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Error reference · Asterisk

Asterisk: No joint capabilities for 'audio' media stream between our configuration(alaw) and…

No joint capabilities for 'audio' media stream between our configuration(alaw) and incoming SDP(ulaw|telephone-event)

What it means

The other side offered codecs, none of which is allowed on this endpoint, so the call fails with 488 Not Acceptable Here.

Why it happens

  • The endpoint allows only alaw, the provider sends only ulaw (or G.729).
  • disallow=all without a following allow=.
  • Different codec order expectations on a transfer or bridge.

How to fix it

  1. Allow the codec the other side offers (allow=alaw,ulaw).
  2. Check the offer/answer in the SDP analyzer.
  3. Install a codec module (codec_g729) if the provider insists on it.

Useful tools

SDP analyzer · SIP 488 Not Acceptable Here

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