API 2500

[Sheep]

Got a new API 2500 -- I'm having issues. Here's my chain:

PT LE on a Digi 002
API 2500
STC-8
HEDD
L2
Masterlink

Even when the API's in bypass mode it's like the center of the stereo spectrum has been vacuumed out (it's VERY noticeable -- a huge hole). I've tried hooking it up in various combinations and using the link feature at various positions, but the hole is still there. If I pan an instrument dead center, it sounds like it's coming from both speakers equally, but nada in the middle. When I remove the API completely from the chain, the hole disappears.

Am I missing something simple or is the unit probably just defective?? Thanks!

[Rail Jon Rogut]

Check for a cable wired out of phase.

Rail