Issue with EXP making odd sound (2 replies)

I'm not sure if this is a marlin problem or an issue with my board.

I swapped my last board out because the Z driver quit working.

Over TFT everything seems to work on this one and I can home/move all axis as expected.

The only issue is when I hook up the EXP1 to the EXP3 on the TFT35 E3 touch screen it came with.

It instantly starts making this clicking/beeping that sounds like a metronome.

When I can actually get it to the classic menu it's bounding in and out of the menu like I'm clicking the button.

It does the same thing no matter if I use a new or old cable and does it on the stock display as well.

None of the pins are shorted together on the board connector when I check with a multimeter.

I think I have all the options enabled it said I would need for the screen including #define CR10_STOCKDISPLAY

Anyone seen anything like this before?

Not really the end of the world I guess, but kind of lame I can't use the classic mode.

Here is a link with sound: [imgur.com]

Thanks.