Interact series 2 speed controller problem

Good mornnig men,

my miller has started playing up yesterday, the speed controller was working ok untill i went for lunch,

on return not playing ball,


with air connected and i choose either up or down speed, but when i press the button the indicator only moves a hundred revs or so if i'm lucky then stops, if i keep pressing it in quick sucesion, the air valve is working ok, and the speed indicator judders a bit but wont move,

also there is a lot of air escaping from what must be a safety blow off valve on the rear of the black plastic air valve housing,

this was not happening prior to this problem as the compresser is running almost constant due to air loss

it stikes me that this air loss is the root of the problem, so can it be a leeky seal in a the valve somewhere,

anyone any ideas . i dont want to start dismantling the valve unitll i have more ideas of what to look at,

btw the air brake is working fine and this shares the same air supply [obviously]

any help would be appreciated,

many thanks carl

You got contraves speed drive on that machine?

You mention an air leak - if you have a leak, is your compressor keeping up (is your receiver tank emptying too quickly due to the leak?)