BUNDLE and the same RTP header extension ID pointing to different uris

Hi, Firefox creates a SDP offer as follows (simplified):


a=group:BUNDLE sdparta_0 sdparta_1

m=audio 9 UDP/TLS/RTP/SAVPF 109 9 0 8
a=extmap:1 urn:ietf:params:rtp-hdrext:ssrc-audio-level
a=extmap:2 urn:ietf:params:rtp-hdrext:sdes:rtp-stream-id

m=video 9 UDP/TLS/RTP/SAVPF 120 121 126 97
a=extmap:1 urn:ietf:params:rtp-hdrext:sdes:rtp-stream-id


This is, it uses the same id 1 to indicate different RTP header
extensions within the *same* RTP session (as both, the audio and the
video streams, are bundled).

AFAIR this is a bug because the ID of RTP header extensions within the
same RTP session must be unique. Am I wrong?

-- 
Iñaki Baz Castillo
<ibc@aliax.net>