Have you checked your RAM usage while this is occuring ?
RAM usage is pretty normal in this issue.
It's like there are some infinite loop (or very many times loop) happen after input/delete character(s) in the MetaEdtior.
I think it's better to look up code at the check functions that do checking after input/delete and do loop which would have chance to repeat many times.
Then the check function that produce FALSE value may be our evil.