My ignition has been acting funny. Every once in a while during the past few months the bell that tells you the key is still in the ignition has gone off even though the key was not in the ignition. It goes off after a few seconds. Now, my radio frequently shuts off while the car is running and then comes on after a bit. This morning, the car wouldn't start because the battery was too weak, so I suspect the issue is causing a current draw. I'm guessing the problem is either the ignition lock cylinder or the switch, but don't know how to diagnose. Any help would be greatly appreciated.