charging the FPZ

[CaptNumbNutz]

A little update,  I have used the USB port on my PC, my phone charger and the raspberry pi power cable that it came with, and all turn on my screen while charging. I do have foam separating the display from the board. But upon further inspection , I noticed when the fpz is off, and the batteries are hooked up, I hear a rapid ticking sound . I removed the pi and it goes away. But as soon as I plug it it I hear it again.

I did notice that my battery has drained from over the course of a day just sitting powered off. Maybe that's the sound I have been hearing?

-Rapid ticking sound
-only audible when power applied, either with batteries or plug
-Screen turns on when charging.
-Battery drains over the course of a day even when not turned on.

Any chance it could be a short?

I would double check your soldering on the GPIO pins on the Pi. That is the most likely culprit since that involves user assembly. Next I would check the board itself, especially in and around the ribbon cable. Check for scorch marks. I'm guessing something is arcing to ground that involves the display electronics.

I could be wrong and the noise is actually emanating from the speaker. I would still check all of your solder joints on the GPIO header.

-EDIT-
Got to hear the video and the sound OP was talking about. It's not arcing electricity or short. It's a very low humming noise, the kind that old TV's used to make. You can also see the LCD itself scanning left to right, but I'm not sure if it actually does this or if it's nearing the same refresh sync rate as the camera. When he turns it around you can hear the noise more prominently near the cartridge opening and not from the front where the speaker is. Is it possible the inductor or something else is making noise kind of like coil whine? That being said, coil whine would simply be a symptom of the issue.

I'm stumped. I'd say it's the LCD or the FPZ main board as I have never heard that sound out of a Pi. No way to tell without spares on hand.