I am able connect to irc.rizon.io and join channels with no issues in mIRC v7.44.
Are you using anti-virus software? If you disable it completely and then run mIRC and connect, do you see the same issue?
If you open the mIRC Options/Connect/Options/Ports dialog, are the UPnP options enabled? If you disable them and then try again, do you see the same issue?
