Misfire on number three cylinder

My number three cylinder cuts off when the car reaches the MIVEC cross over point at 5,500 rpm's. The car sputters for a number of seconds before 'recovering' and return running on all four cylinders on the low cam.

The problem use to be intermittent as it would only do it sometimes when reaching the MIVEC point or if I short shift above the 5,500 but of recent, the problem occurs every time the car crosses over to the high cam.

I have changed plugs, coil packs, fuel filter, cleaned injectors, changed fuel pump and cleaned the MIVEC solenoid. I also removed a small dent from the sump pan to ensure oil flow was adequate.