I have a fused electronic distribution block (led v. readout, splits to 4 fused terminals)

The thing is, whenever I hook it up with power it squeals constantly like something is wrong. When I first got it I thought it that it didn't have a fuse. I didnt have a fuse so I bridged the connections to see if the beeping would stop with a wire and it kept doing it.

I cant remember the brand of them, otherwise id look up a .pdf manual or something.