New videobridge added OK but fails

Help please… I previously had a functional JMS with additional scaling JVBs working (on AWS) that stopped working after doing the recent stable update inc Lobby feature.

I’ve scrapped the idea of auto-scaling and am now urgently trying to add a single additional JVB, following this guide to the letter, but I’m getting the dreaded “Something went wrong” failure…

The jicofo logs confirm that the new videobridge is successfully added and it shows as an operational bridge when I curl the stats, however when trying to join a conference (second participant) it fails with log entries such as:

SEVERE: [96] org.jitsi.jicofo.JitsiMeetConferenceImpl.log() One of our bridges failed
SEVERE: [96] org.jitsi.jicofo.JitsiMeetConferenceImpl.log() Can not invite participant – no bridge available.
SEVERE: [103] org.jitsi.jicofo.AbstractChannelAllocator.log() jvbbrewery@internal.auth.urlremoved/jvb2 - failed to allocate channels, will consider the bridge faulty: Timed out waiting for a response.
org.jitsi.protocol.xmpp.colibri.exception.TimeoutException: Timed out waiting for a response.
at org.jitsi.impl.protocol.xmpp.colibri.ColibriConferenceImpl.maybeThrowOperationFailed(
at org.jitsi.impl.protocol.xmpp.colibri.ColibriConferenceImpl.createColibriChannels(
at org.jitsi.protocol.xmpp.colibri.ColibriConference.createColibriChannels(
at org.jitsi.jicofo.ParticipantChannelAllocator.doAllocateChannels(
at org.jitsi.jicofo.AbstractChannelAllocator.allocateChannels(
at org.jitsi.jicofo.AbstractChannelAllocator.doRun(
at java.util.concurrent.Executors$
at java.util.concurrent.ThreadPoolExecutor.runWorker(
at java.util.concurrent.ThreadPoolExecutor$

Not sure what to do to get this working and would appreciate any help!