With the switch in the 12 volt position the M2200 should come on when the processor comes on. Make sure you are using a 3.5 mm MONO plug vice a stereo version. The mono plug has two sections, vice three on the stereo version. If that doesn't solve the issue then check the voltage of the processor output. M2200 should function with voltages between 6-35 vdc per the manual. If you want to see the manual it is still available under the products page.
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Music system
Model 990/7500/Magnepan 1.6 QRs/Technics SL1200 MK2/Aperion S-12 Subwoofer/OWA3/Sony NS75H DVD
APC H15 Power Conditioner

TV System
Large Advent Loudspeakers/ Polk center/Monoprice surrounds/Panasonic Viera 42 inch/Onkyo HT-RC260/Sony BDP S590/Directv


Home Theater System
Onkyo PR-SC886/Outlaw 7125 Klipsch RF-82 L/R,RC-62 center, RB-35 SR/SL, BENQ HT1075, Outlaw LFM1-EX/OPPO BDP-83/Directv
Harmony ONE
Blue Jeans and Monoprice interconnects
APC H15 Power Conditioner