Board Thread:Versus Debates/@comment-26958911-20151010214426/@comment-26636534-20160102155710

However, Jiraiya's genjutsu is more dynamic and being sound based it doesn't have to be activated close to Itachi.

P.S. Though it is not confirmed, it is very very unlikely that Itachi can reflect a super powerful, extremely chakra taxing sage powered genjutsu.