Scala plugin slows down Java parsing / editing

I've got a 500 LOC Java file which does not reference any Scala code. With the Scala plugin enabled, editing this file is terribly slow - lags up to several seconds. It takes about 5 seconds for Idea to parse/typecheck the file. Funny, it doesn't happen for most other Java files in the project. With the Scala plugin disabled, the exactly same file typechecks in below 0.5 second and there are no visible lags when editing it. I have language injections in Scala plugin already disabled.

Profiling didn't uncover anything interesting - all time seems to be spent in intellij code, not plugin code. If you could tell me what to focus on, I could do more profiling (or tell me what to look for).
Any ideas?

Thanks,
Piotr

PS. Versions:
IDEA Community 13.0.2  133.696
Java: 7u51
Scala plugin: 0.30.375

Previous update of IntelliJ IDEA 13.0.2 with previous version of Scala plugin (I guess 0.29.x) also had that problem.