diff --git a/libraries/AP_Menu/AP_Menu.cpp b/libraries/AP_Menu/AP_Menu.cpp
index af68177ecf..aa3a0e338b 100644
--- a/libraries/AP_Menu/AP_Menu.cpp
+++ b/libraries/AP_Menu/AP_Menu.cpp
@@ -58,8 +58,10 @@ Menu::run(void)
         _port->printf_P(PSTR("%S] "), FPSTR(_prompt));
         for (;; ) {
             c = _port->read();
-            if (-1 == c)
+            if (-1 == c) {
+                hal.scheduler->delay(20);
                 continue;
+            }
             // carriage return -> process command
             if ('\r' == c || '\n' == c) {
                 _inbuf[len] = '\0';