Might help to troubleshoot if you have the same scripts.

I'm using all of the mtwitch.* scripts (and the jsonForMirc one) from this page:

https://github.com/SReject/mTwitch

Also have one called mtwitch.isupport but not sure where I got that from. Might be a discontinued script from there or one they offer but from another location. I have a few custom scripts too, but I have a hunch that it's one of those triggering the issue, possibly even the jsonForMirc one.