In the meantime: if you have catching enabled for URLS or Emails in Options/IRC/Catcher, please uncheck them. I am trying to narrow down potential causes and there was a big internal change in the URL/Email catcher in v7.46. Does disabling these options resolve the issue?
Any update? Not sure if you saw it before, but in response to this, I mentioned that neither were checked (were already unchecked).
Could it be related to the OS being used? I'm using WS2012R2. Maybe there's an unknown issue that make a difference. I'm sure it is also related to scripting on some level, but perhaps something in the scripts is a symptom vs being a cause. Just tossing it out there in hopes of it giving you ideas on what it could be.