Stabilize tshark installation
diff --git a/.travis/install.sh b/.travis/install.sh
index 98747a8..9fb6d04 100644
--- a/.travis/install.sh
+++ b/.travis/install.sh
@@ -17,6 +17,7 @@
 # Install wireshark data
 if [ "$TRAVIS_OS_NAME" = "linux" ] && [ "$TRAVIS_SUDO" = "true" ]
 then
+  sudo apt-get update
   sudo apt-get -qy install tshark
   sudo apt-get -qy install can-utils build-essential linux-headers-$(uname -r);
 fi