I guess you didn't search the forum before posting this ? If you had done you would have found:
As for your scrambled picture I would suspect the box you bought is not stripping out the HDCP signal. It's a bit on the cheap side, the one most people use (HDFury) costs a couple of hundred dollars. Might be worth contacting the user (Martin Katz) that I built that custom remote for to see what he is using.
I have a Slingbox 350 and I can't get it to work properly. First of all I have Cox cable and my cable box isn't listed in the directory. It's a Cox MiniBox and here are 2 pictures of it. Also since the cable box only supports coax and HDMI output and the Slingbox only supports composite and component inputs I bought an HDMI to composite adapter. KanexPro HDMI to Component with Audio Converter HDRGBRL - Newegg.com The audio works great but the picture is scrambled. I also attached a screenshot of what every channel looks like. Is there a way that I can get this to work? I called Cox and they told me that the Mini Box I have isn't encrypted with HDCP. My next assumption is the HDMI to composite adapter.