Aquatronics 1+ Midnight crisis shower turns hot 2 cold or stays cold ?

My Aquatronics 1+ is 6 Months old.
It works fine during the day but comes midnight the water turns either boiling hot or freezing cold at intervals or just remains constantly cold

I am not on economy 7, the water flow seems fine. No one i have consulted seems to know where the problem comes from, could anyone be of assistance?