1997 BMW Z3 Intermittent Door Lock Issue

I saw another door handle question posted here for the Z3, so in the interest of keeping things organized, will post it in this category. There wasn't really a good category for it.

I am having intermittent issues turning the key in both the driver and passengers sides door locks. It is currently cold outside. I do not have engine starting issues, just door locking issues in which I am unable to get the key to turn. Sometimes the issue is with s locking, sometime it is with unlocking, often both, often both passenger and drivers side, currently its pretty bad. If the key turns, the door will lock or unlock, but the issue is often the key simply wont turn. Any help appreciated.