Igmpproxy needs to be restarted after a client disconnect


I am using igmpproxy for tvheadend running on one of my server in my network, to connect to multicast streams provided by my ISP.

Up to a few days ago, it was working fine. I could watch streams from tvheadend or from VLC running on another computer (not at the same time though).

Since a few days, it does not work anymore. Basically, it works, I can switch from one stream to another without any problem. Then if I stop playing, I cannot reconnect ever to any stream on subsequent play. Only solution is to stop igmpproxy, let it stopped for a few seconds and restart it. Only then the first client will be able to reconnect to a multicast stream and switch channel until it disconnects.

My configuration is the following and hast not changed:

config igmpproxy
        option quickleave 1
        option verbose 1 #(none, minimal[default], more, maximum)

config phyint
        option network wan 
        option zone wan 
        option direction upstream
        list altnet

config phyint
        option network lan 
        option zone lan 
        option direction downstream

Any idea what could be the issue?