Knocking on the doors

[all black]

So I'm fooling around on Night 4. I shut both doors and don't check the cameras at all (Basically just being idle). Soon I heard the sound of someone knocking on my door, which I found odd since Freddy was still on stage. Bonnie and Chica were both out and about, but I thought only Freddy could knock on the door. I know for a fact it wasn't Foxy since he bangs on the door instead of knocking, and for those of you who might still think it was Foxy, I closed the left door, didn't check the cameras for a little bit, and still heard knocking, which had to have come from the right door. But only Chica was there, so is it possible that Bonnie and Chica have the ability to knock on the office doors as well as Freddy? (The knock seems to come from the right door but could easily come from Bonnie as well since it's kinda hard to discern where it's coming from.)

[Fortuna]

"and for those of you who might still think it was Foxy, I closed the left door, didn't check the cameras for a little bit, and still heard knocking, which had to have come from the right door."

Foxy comes more often when you don't check on him, you had the left door closed, Foxy only comes from the left. What confuses me here is that you closed the left door but you say the knocking came from the right? How?

[all black]

It's hard to explain. I know it can't be Foxy since it's not the same sound he makes when knocking on the door. I'm not certain which door it's coming from. When both doors are closed I hear it, when one door is open I hear it. Doesn't matter which door is open, if I'm idle I still hear knocking. Also, when Foxy comes-a banging on the left door it drains power every time, but the knocking sound I hear doesn't drain any power.

[Fortuna]

Did it perhaps sound like this?
http://freddy-fazbears-pizza.wikia.com/wiki/File:DOOR_POUNDING_ME_D0291401.ogg

Or did it sound more like this?
http://freddy-fazbears-pizza.wikia.com/wiki/File:Knock2.ogg

[Robert Simpleton]

When exactly did this happen?

It's worth pointing out that on the Night 4 phone call, you can hear knocking several times in the phone call before it ends (though I believe this is similar to the knocking Foxy makes). It happens around the time Phone Guy says "Hey, listen, I may not be around tomorrow..." or something along those lines.

Freddy also cannot knock on the door from my knowledge.

[Cybersquid overlord]

No that was me knocking on the door to ask you stupid questions.

[all black]

Sorry for taking so long to reply. Had to go grocery shopping. After some more experimenting I've realized that the knocking is indeed Foxy because the power does in fact drain every time its heard. Don't know how I didn't notice that before. I kept the left door open while closing the right door and didn't hear the knocking so that pretty much confirms it's Foxy's doing. Disregard everything I've said above, I'm just going crazy o'er here and imagining things.

Probably from playing the game too much.