about 5 months ago I replaced my starter because it wasn't disengaging and now I have the same problem, before I go and buy another is there anything else I should check as I feel like it shouldn't of gone bad in 5 months. its a 03 blobeye wrx. any input is appreciated.

 

could be a sticky ignition switch not reseating/reseting itself. The only was to test is to see if there is voltage still going to the starter motor after the key returns to the run position (after you turn the key to start the car it goes back to number 2 position etc) HOWEVER im not sure that it is safe to start measuring voltage on that circuit, i would think it takes a fair amount of power to start a car. If irc the ignition goes to a relay and the relay goes to the starter so could also be a sticky relay. ONCE AGAIN if you are unsure if it is safe to measure voltages then check with someone qualified.