IpCamera Discovery error

Running the ipCamera discovery features provides the following error:

17:17:08.875 [ERROR] [internal.DiscoveryServiceRegistryImpl] - Cannot trigger scan for thing types '[ipcamera:foscam, ipcamera:onvif, ipcamera:hikvision, ipcamera:amcrest, ipcamera:instar, ipcamera:dahua, ipcamera:generic, ipcamera:doorbird]' on 'IpCameraDiscoveryService'!
io.netty.channel.ChannelPipelineException: org.openhab.binding.ipcamera.internal.onvif.OnvifDiscovery$2 is not a @Sharable handler, so can't be added or removed multiple times.
        at io.netty.channel.DefaultChannelPipeline.checkMultiplicity(DefaultChannelPipeline.java:604) ~[?:?]
        at io.netty.channel.DefaultChannelPipeline.addLast(DefaultChannelPipeline.java:202) ~[?:?]
        at io.netty.channel.DefaultChannelPipeline.addLast(DefaultChannelPipeline.java:385) ~[?:?]
        at io.netty.channel.DefaultChannelPipeline.addLast(DefaultChannelPipeline.java:372) ~[?:?]
        at io.netty.bootstrap.Bootstrap.init(Bootstrap.java:259) ~[?:?]

Do you have any idea on the reason?

My install:
OH3.0.1 version running on Docker running on synology DS916+ and DSM7 / Java11

Same thing on OpenHab 3.2 Release Version on a Pi4B running openhabian

Same here. openhab 3.4.0 running on debian 11.6 ( RPI ) …

The same on Openhab 3.4.2 on a PI3 raspbian. Is there a know solution? I tried it on an other test system and there was no problem. I think the following is part of the problem:

[INFO ] [mera.internal.handler.IpCameraHandler] - The alarm stream was not running for camera, re-starting it now

That info log line is not an issue unless it reoccurs. It happens every time a camera first connects and the alarm watching thread is not running.

Do you see any signs that two discovery scans are running at the same time? Openhab has background and also manually started scans so it may be that a scan is locked up perhaps, you would need to look at Debug level logs to see what was happening.