diff --git a/Build-Linux.md b/Build-Linux.md
index 69f12a6..3620a7b 100644
--- a/Build-Linux.md
+++ b/Build-Linux.md
@@ -34,7 +34,7 @@ build$ SoapySDRUtil --info #test SoapySDR install
 $ git clone https://github.com/jgaeddert/liquid-dsp
 liquid-dsp$ cd liquid-dsp
 liquid-dsp$ ./bootstrap.sh
-liquid-dsp$ CFLAGS="-march=native" ./configure --enable-fftoverride 
+liquid-dsp$ CFLAGS="-march=native -O3" ./configure --enable-fftoverride 
 liquid-dsp$ make -j4
 liquid-dsp$ sudo make install
 liquid-dsp$ sudo ldconfig