diff --git a/doc/AbletonPush2MIDIDisplayInterface.asc b/doc/AbletonPush2MIDIDisplayInterface.asc
index 34315a1..312dd4a 100644
--- a/doc/AbletonPush2MIDIDisplayInterface.asc
+++ b/doc/AbletonPush2MIDIDisplayInterface.asc
@@ -687,6 +687,11 @@ After a MIDI stop message (+0xFC+), the animations continue to run at the
 last received tempo. If the host never sent a MIDI start message, the animations
 run at a tempo of 120 bpm.
 
+NOTE: In User mode, MIDI system real time messages (start, stop, continue, clock)
+must be sent on Port 2, as Port 1 MIDI messages are ignored in User mode.
+If no MIDI start message has been received on the active port, animations will not
+run until a MIDI start message is sent.
+
 As usual with MIDI-over-USB interfaces, system real time
 messages should not be sent in the middle of other MIDI messages.