Sending AES67 to Dante devices

[Elliott Balsley]

Hello everyone.  I'm having trouble routing an AES67 stream from a Dolby cinema processor into Dante devices.  I've done this before with other AES67 sources and it works fine, but there must be something peculiar about this particular source.  Unfortunately Dante Controller has a very minimal log file, so I'm looking for any advice on how to troubleshoot this.

The source does not advertise SAP, so I'm using Rav2Sap to add that.  Dante Controller sees the transmitter and makes a subscription with no errors, but it does not show the green speaker icons, and the Dante receiver just gets silence.  Any ideas what would cause that behavior?  Could it be something wrong with PTP?  I've tried changing PTP priorities to make each device the grandmaster, but that doesn't make any difference.

This stream works fine in both gstreamer, ffmpeg, and the Ravenna ALSA driver.  Example ffmpeg command I use to show volume meters:

ffmpeg -loglevel error -protocol_whitelist file,rtp,udp -i dolby1.sdp -filter_complex "showvolume=t=0:dm=1:ds=log" -f sdl -

In Wireshark I can see the SAP announcement roughly every 25 seconds (it varies).  The SDP file looks like this:

v=0
o=- 3 0 IN IP4 10.49.51.51
s=CP950A
c=IN IP4 239.69.83.67/32
t=0 0
m=audio 6518 RTP/AVP 96
a=clock-domain:PTPv2 0
a=rtpmap:96 L24/48000/8
a=recvonly
a=framecount:48
a=sync-time:0
a=ptime:1
a=ts-refclk:ptp=IEEE1588-2008:00-60-DB-FF-FE-01-02-C8:0
a=mediaclk:direct=0