2000 silverado power door locks

This truck is driving me insane! The door locks keeping jamming up. I mean you can't move it with the remote, using the switches on the door or using you key from outside. It either jams locked or unlocked.

My husband has replaced the actuators on both sides once already. We got the actuator from a parts store, not the dealer, for 40 bucks. It is made by a popular replacement part dealer, out of one of the most known auto parts stores. (I don't know if I can say the names!)

So now we are in the same place we were 3 months ago. The dealer said that they only sell it as the whole lock assembly for 150 bucks. (the arms, actuator, etc..) What should we do? Could it be we should not of gone the cheap route the first time around? We are at our wits end! Should we replace the whole assembly and see what happens. Could it be more than just the actuator? Has anyone here with a 2000 Silverado ever had this problem?

Thanks for any suggestions anyone might have! They are appreciated!

Does anyone have any info on this? Please!

Have you checked all of the linkage? If its possible, check it and grease it anywhere it contacts something.