diff --git a/README.md b/README.md
index dc2e554..3c30f03 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@ IRMC stands for Internet Relay Morse Code and is an implementation of [MOIP](htt
 
 # Building 
 ## On Linux
-Install portaudio, i.e.:  sudo apt-get install libportaudio-dev
+Install portaudio, i.e.:  sudo apt-get install libportaudio-dev portaudio19-dev
 
 # Hardware interface options
 A good description on how to build different interfaces (telegraph key, sounder or both)