Ok. So I am setting up a 4U Rack in My Studio. 2 Compressors, a Stereo Enhancer and a Power Strip. When I plug my XLR Condenser Mic (MXL 4000) directly to my mixer, all is fine. But as soon as I try to route the Mic to a compressor then to the Mixer I get nothing. I have tried all the racks at the same time, tried each by itself, Tried both channels on each rackmount individually AND I tested ALL mic cables. Still nothing! All 3 Racks are brand new so I figure they ALL cant be Faulty. I must be doing something wrong. Any ideas would greatly help me out. Thanks.
(Rack1 - dbx266xs / Rack2 - Behringer Composer Pro XL / Rack3 - Sonic Exciter XS3040)
(Mixer - Behringer X1222USB [Switching to a Yamaha MG166CXUSB in 2 weeks]
None of these ouboard processors provide 48v phantom power. You need that for your condenser to transmit sound. The mixer provides it, thus why you are getting sound that way but not the other. You can't run a condenser directly into a compressor without some type of preamp stage.
If you are saying that you are running the outboard on the insert, then something must be wrong with send/return levels. Or even the insert jack itself.