I have a same problem with Mini Recorder. No chance to get HDMI signal. (MacBookPro 15 retina 2.3 GHz i7, 16 GB RAM)
BUT!
Even I was not able to get the signal from my CANON 550D or Panasonic GH2 - I found one source which WORKS!! It is strange, but
from my iPad2 with AV output connector (including HDMI) I got
a nice live stream with setting "720p 60".
I had chance to test SDI input as well and it works fine for Panasonic P2 and ICONIX RH1. So no problem with SDI inputs at all.
Please, can anyone with problem with HDMI test connection with iPad as well, so we can compare? What I feel as problem is that
Mini Recorder don't "communicate" with connected HDMI devices. So if I try to connect for example my CANON 550D it even don't "switch the screen" as when I connect it to HDMI plasma. So because camera doesn't recognize that is something connected it doesn't even send any output to HDMI. (and because iPad maybe don't try to establish any two way communication and just "feed" connected HDMI" - it works). I read on this forum some post describing, that Mini Recorder connected to computer output (for example HDMI from MacBook) is not recognized as new "monitor". And because I have same experience with this, it gives me this idea of "no communication from the side of Mini Recorder".
My next try will be to skip this possible disadvantage with GEFEN HDMI Detective Plus (
http://www.gefen.com/kvm/dproduct.jsp?prod_id=8005). Device which simulate EDID of connected device. So I will connect my CANON to Detective (camera will probably recognize it as "some useful output" and will start to output signal thru HDMI) and then from Detective via HDMI to Mini Recorder. I have ordered it last week, so next week I will have a chance to give a real try. And I will write there, if it helps or not.
Or maybe BMD guys will produce some new firmware or software update before that (I will prefer this solution)