I'm building a GMRS repeater with two Wouxun KG-1000G units. Doing some bench testing and noticed that when I put my Nissei RS-50 SWR meter inline with  an XLT 50W dummy load, I get SWR 1.02 and power 42W. But when I run the signal through the XLT DP-GMRS-50 duplex and measure to the same load, I get SWR 1.0 and power 9W. Is it customary to lose that much power through a Duplexer?