You have got a ghost !!! Seriously , strange fault . As it is only affecting one window , the only thing I can suggest is to check switch / wiring for that side . You could disconnect switch and see if it is ok then . Either that or check wiring at window motor .Really a case of stripping down and tracing through circuit for fault .Dont know if a faulty relay would cause this intermittent fault . I am not an auto electrician , so this is all I can suggest to help .
One of the common faults in door electrics is where the wiring passes from vehicle to door at this point wires have a habit of breaking and end up moving about and touching intermitantly.
Failing that i'm pretty sure that the windows can be accessed by using a code reader which will no dought have a fault logged