diff --git a/.travis.yml b/.travis.yml
index 788ab8d..d48df94 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -44,7 +44,7 @@ matrix:
   
 before_install:
     - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew update; brew install libusb fftw qt5; export CMAKE_PREFIX_PATH=$(brew --prefix qt5); fi
-    - if [[ "$TRAVIS_OS_NAME" != "osx" ]]; then sudo add-apt-repository ppa:beineri/opt-qt542-trusty;sudo apt-get -qq update; sudo apt-get --yes install -qq qt54base; fi
+    - if [[ "$TRAVIS_OS_NAME" != "osx" ]]; then sudo add-apt-repository -y ppa:beineri/opt-qt542-trusty;sudo apt-get -qq update; sudo apt-get --yes install -qq qt54base; fi
 
 before_script:
     - QTDIR="/opt/qt55"