No audio from some participants. Video works

Hi,
I have encountered an issue where some users will connect to a conference. We can see their video but can’t their audio.

Here’s the JVB log with severe issues during the conference:

> 2020-06-26 00:28:36.200 WARNING: [92] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=100, Ssrc=1742423176, SeqNum=30843, M=true, X=true, Ts=4073601414, encodings=
> 2020-06-26 00:28:36.203 WARNING: [92] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=96, Ssrc=456803059, SeqNum=2398, M=true, X=true, Ts=4073601414, encodings=
> 2020-06-26 00:28:36.204 WARNING: [93] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=96, Ssrc=456803059, SeqNum=2399, M=false, X=true, Ts=4073601414, encodings=
> 2020-06-26 00:28:36.210 WARNING: [93] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=96, Ssrc=456803059, SeqNum=2400, M=true, X=true, Ts=4073601414, encodings=
> 2020-06-26 00:28:36.210 WARNING: [93] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=96, Ssrc=456803059, SeqNum=2401, M=false, X=true, Ts=4073601414, encodings=
> 2020-06-26 00:28:36.215 WARNING: [93] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=96, Ssrc=456803059, SeqNum=2402, M=true, X=true, Ts=4073601414, encodings=
> 2020-06-26 00:28:36.216 WARNING: [91] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=96, Ssrc=456803059, SeqNum=2403, M=false, X=true, Ts=4073601414, encodings=
> 2020-06-26 00:28:36.216 WARNING: [91] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=96, Ssrc=456803059, SeqNum=2404, M=true, X=true, Ts=4073601414, encodings=
> 2020-06-26 00:28:36.216 WARNING: [91] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=96, Ssrc=456803059, SeqNum=2405, M=false, X=true, Ts=4073601414, encodings=
> 2020-06-26 00:28:36.216 WARNING: [91] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=96, Ssrc=456803059, SeqNum=2406, M=true, X=true, Ts=4073601414, encodings=
> 2020-06-26 00:28:36.217 WARNING: [91] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=96, Ssrc=456803059, SeqNum=2407, M=false, X=true, Ts=4073601414, encodings=
> 2020-06-26 00:28:36.221 WARNING: [91] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=100, Ssrc=2342550654, SeqNum=21510, M=true, X=true, Ts=2226047257, encodings=
> 2020-06-26 00:28:36.229 WARNING: [89] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=100, Ssrc=1742423176, SeqNum=30844, M=true, X=true, Ts=4073604204, encodings=
> 2020-06-26 00:28:36.230 WARNING: [89] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=96, Ssrc=456803059, SeqNum=2408, M=true, X=true, Ts=4073604204, encodings=
> 2020-06-26 00:28:36.231 WARNING: [89] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] VideoParser.transform#58: Unable to find encoding matching packet! packet=RtpPacket: PT=96, Ssrc=456803059, SeqNum=2409, M=true, X=true, Ts=4073604204, encodings=
> 2020-06-26 00:28:36.243 INFO: [1295] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] Endpoint$7.onReady#882: SCTP connection is ready, creating the Data channel stack
> 2020-06-26 00:28:36.243 INFO: [1295] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] Endpoint$7.onReady#909: Will wait for the remote side to open the data channel.
> 2020-06-26 00:28:36.243 SEVERE: [1291] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] DataChannelStack.onIncomingDataChannelPacket#81: Could not find data channel for sid 0
> 2020-06-26 00:28:36.243 SEVERE: [1291] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] DataChannelStack.onIncomingDataChannelPacket#81: Could not find data channel for sid 0
> 2020-06-26 00:28:36.243 SEVERE: [1291] [confId=f484372deda8df3c epId=7fb26ed6 gid=ff3978 stats_id=Al-jjL conf_name=5313782151] DataChannelStack.onIncomingDataChannelPacket#81: Could not find data channel for sid 0