disco 2 strange lock problem

Hi everyone, so now it's time to ask for my first bit of advice with my newish landy.
The drivers door central locking motor has recently stopped working on key plip. It locks fine on speed lock but won't unlock when ignition is turned off.
It also locks ok with dash switch but won't unlock with the switch.
However 99% of the time it won't lock or unlock from keyfobs meaning I have to use key in door lock method to lock and unlock drivers door. The alarm arms and disarms fine with key fob and all other doors lock / unlock fine with fob.
The only other thing is having purchased a nanocom a few weeks ago ( in preparation for future problems, lol ) I used it to turn speed lock option on. Then for about 1 day the problem disappeared completely, with drivers door locks operating fine. Then later in the day it stopped working and I'm back to using the key to lock / unlock !!
I've looked online for solutions but not really found an answer apart from needing new actuator. If it works on speed lock and dash switch then surely the motors not failed ?
Any help or advice from any members out there would be gratefully received.
Many thanks.

Hi, the door lock actuator is on it's way out, replace it and you'll be ok, on fob operation the voltage to actuators used to be few milivolts lower than on switch or speed lock operation and that can affect a worn actuator's behaviour...they always fail to unlock first then getting worst in time

Thanks for that info. Looks like I need to look on eBay for a replacement.