diff --git a/usr/lib/sysctl.d/990-security-misc.conf b/usr/lib/sysctl.d/990-security-misc.conf
index 3c80e23..fd51343 100644
--- a/usr/lib/sysctl.d/990-security-misc.conf
+++ b/usr/lib/sysctl.d/990-security-misc.conf
@@ -309,7 +309,7 @@ net.ipv6.conf.default.accept_ra=0
 ##
 #net.ipv4.tcp_sack=0
 #net.ipv4.tcp_dsack=0
-net.ipv4.tcp_fack=0
+#net.ipv4.tcp_fack=0
 
 ## Disable TCP timestamps to limit device fingerprinting via system time.
 ##