RE4R01A autobox expert help needed !

[dolb]

HiI have a nissan serena which has a re4r01a box fitted.

I have read some good info on the forums about this box as it is a common fitment but have not found a answer to my problem. :

I have a problem with the line pressure solenoid valve buzzing at 1/4 to 1/2 throttle openings. The noise is caused by rapid opening a closing of the valve.

From throttle voltage output 1.6 volt to 2.5 volts is when it does this.

If gearbox plug is disconected and voltage applied to pin for solenoid it just clicks once as it opens.

Resistance of solenoid is within spec. 4 omhs

If the dropping resistor is unplugged the solenoid buzzes for a second when the ignigtion is turned on but is ok when the throttle is depressed.

Thanks in advance for any help.