File changes break LiveReload

I am using Middleman on Mac OS X 10.9.x. I have noticed that when I delete a file and sometimes when I add or replace a file, that livereload no longer works and I have to restart the server to pick up any changes and to serve the new assets.

What I expect is that when I add/delete/replace a file that the changes should be picked up without a server restart. Has anyone else come across this issue?

My Gemfile is below if it helps

# If you do not have OpenSSL installed, update
# the following line to use "http://" instead
source 'http://rubygems.org'

gem "middleman", "~>3.3.7"

# Live-reloading plugin
gem "middleman-livereload", "~> 3.1.0"

# For faster file watcher updates on Windows:
gem "wdm", "~> 0.1.0", :platforms => [:mswin, :mingw]

# Windows does not come with time zone data
gem "tzinfo-data", platforms: [:mswin, :mingw]


# Assets
gem "middleman-favicon-maker", "~> 3.7"

# Optimisation
gem "middleman-minify-html", "~> 3.4.0"
gem "middleman-imageoptim", "~> 0.2.0"

# deploy
gem 'middleman-deploy', '~> 1.0', :platforms => :ruby

gem "bourbon"