Help: Stingray Special shorting out

I bought this bass used from guitar center and it arrived yesterday. The bass looks and plays great, however when I plugged it in I noticed there was no sound. I put 2 new 9v batteries in and still nothing. Then I noticed if I opened one side of the battery compartment, sound would come through and when I closed it, it would stop again. Then the clip that holds the battery down broke off….so I ordered another battery box from Ernie Ball. They are great to deal with, by the way!

Any idea what could be causing this? I uploaded a video to show what’s happening: Stingray battery box – YouTube