SIP 488 Not Acceptable Here

AsteriskRFC 3261 §21.4.26

The destination accepted the request but cannot honour the SDP offer. The classic codec-mismatch error: the offered codecs don't intersect the callee's allow-list.

Common causes on Asterisk

  • Codec mismatch (e.g. caller G.722 only, callee G.711 only)
  • Transcoder offline or not configured
  • SRTP required by one side but TLS/SIPS missing
  • Wrong RTP IP/port from a NAT-broken UA

Asterisk-specific note

On Asterisk PJSIP, check `allow=` on the endpoint and any `codec_pref` in `pjsip.conf`. Also confirm `disallow=all` precedes `allow=` lines so the codec set is what you think it is.

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Same error on a different vendor

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