We bought this house a few months ago, and there is a very interesting problem with the ceiling light in the back room. The ceiling light is turned on or off using one of two switches. One switch is in the kitchen along the door frame, and the other is in the back room on the wall beside the door. The problem that I am having is that the light is caught up in some strange state where one switch only dims it, or barely turns it on, while the other works correctly in an on off fashion as one would expect. If I flip both switches off then go back to the one that was working, it starts to behave like the other one, and only brings it up to a dim state when trying to flip it on. In other words, either switch can be bugged, depending upon the orientation of its partner switch. Which ever switch is currently "the odd switch out", appears to act as a dimmer, and it's a dimmer that cannot go to full brightness.
When either switch is in "the bugged state", both switches produce a low "humming" sound.
I'm pretty sure that something is off about the wiring. My question is, what is this called? I've tried Googling, but I'm not sure what the correct terminology should be that would help me find a video, or solution. Also, if someone is experienced in this specific problem, can you explain why it's happening, and how I could go about fixing it?
Expected Behavior: Light switch A or B turning on or off the ceiling light, regardless of the switches on or off state; for either switch to not dim the light at all.