Meteor not always auto reloading on save

We have a Meteor project on 1.5.1 that’s been going for years. Until a few weeks ago I never saw any issues with the hot reloading, but recently I’ve been seeing that we do a save and Meteor isn’t aware of the change and is showing errors such as template does not exist. If we then hard restart the local development server things work.

This doesn’t happen often, but happening enough that it’s becoming a worry and slowing our developers down when they think the error is with their code when really it’s because Meteor didn’t hot reload properly.

Anyone else had this issue and any ideas on how to fix this?