patch 8.1.1507: sound test still fails on Travis

Problem:    Sound test still fails on Travis.
Solution:   Try another dummy sound approach.
diff --git a/.travis.yml b/.travis.yml
index 4e7df28..407ee72 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -121,25 +121,16 @@
     if [[ "${TRAVIS_OS_NAME}" = "linux" ]] && [[ "${CC}" = "clang" ]]; then
       ln -sf "$(which llvm-cov)" /home/travis/bin/gcov
     fi
-  # Should make sound work (might not all be needed)
-  - |
-    if [[ "${TRAVIS_OS_NAME}" = "linux" ]]; then
-      sudo apt-get update -qq
-      sudo usermod -a -G audio travis
-      sudo apt-get install -y portaudio19-dev
-      sudo apt-get install -y libasound2-dev alsa-utils alsa-oss
-      sudo bash test/prep-dummy-soundcard.sh
-      sudo apt-get install -y lame
-    fi
 
 before_script:
   # Start virtual framebuffer to be able to test the GUI. Does not work on OS X.
+  # Install dummy device for sound.
   - |
     if [[ "${TRAVIS_OS_NAME}" = "linux" ]]; then
       export DISPLAY=:99.0
       sh -e /etc/init.d/xvfb start && sleep 3
-      # pretend to play sound
-      export AUDIODEV=null
+      sudo modprobe snd-dummy
+      sudo usermod -a -G audio $USER
     fi
 
 script:
diff --git a/src/version.c b/src/version.c
index 5c12872..6b6fd19 100644
--- a/src/version.c
+++ b/src/version.c
@@ -778,6 +778,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1507,
+/**/
     1506,
 /**/
     1505,