I am confused..what is the difference between MMHR and SmartLink as I thought -- and wrongly so -- that both were CAT5 inputs for the CAT5 output on devices such as the HD621...

Audio: Triad Monitor Golds, Surround Golds, Silver Subwoofers; Procella P-18 Subwoofer; QSC DCA 16622s, 1644, 3422, BASIS 922uz; ADA MACH IV B
Other: APC S-15s; Crestron
Sources and Video: Ran out of characters .....................