Dimmer actuator problems

[omar@rafskilti.is]

I used several dimmer actuators from Merten for one of my projects.A 500 watt universal piece fairly simple. the problem is that the output from the actuator fluctuates on every single one of them regardless of type of load, size of load or which of three phases of the 3N 400/230V supply is used. I have gone through the tedious buisness of monitoring every possible value on the power supply :voltage, currents, Wattage, Harmonics but with no positive result as to finding what could be causing this. The fluctuations are 1-3 times per minute measuring up to 30+ volts, with a 35% value setting on the actuator. Does anyone Know what could be going on here?