Reply to MF LED MOD - but no MIDI clock on!??!

i have no technical skills other than what this website and the members have taught me .
I have just completed the LED MOD but noticed having the MIDI clock on was effecting the way I sync tracks. Once I turned it off the LED remained on and started a new flashing pattern, one quick and one slow...
anyone experience this? is this a glitch?
everything is tested and still working fine.

here's the vid