I just installed Sirus last week with the little black antenna and it works fine. My extra cable is all in a coil and reception is clear! I did notice however that the antenna worked best where it could pick up the signal from a low level line of sight. I dont know where their satellite is but that little black antenna did not like anything in its way!

I didn't mean to imply that it wouldn't work at all...........but it is what it is.

The antenna prefers or may require a "ground plane". The ground plane can be an 8"x8" aluminum or S/steel plate, mounted on top of the deck w/the antenna centered on the plate. Or,the plate can be mounted directly under the antenna on the inside of the deck. For more performance, connect the plate to the boat negative ground. You may even have to connect to the sea strainer for a water ground. However,not sure about electrolysis.

A simple test of the above: connect a wire to the antenna lead and throw the other end in the water.

Your getting signal and the antenna isnt even outside the cabin? I once saw a boat that was in a bad accident that ripped out the side and I saw what I thought was a GPS or Sirius antena that was mounted under the deck. Thought that was odd at the time but now Im thinking hmmm.

I have a sirius setup on my boat also, my antenna is located under my wind shield, ans my reception is also crappy. I was told that sirius makes a marine antenna, and this should solve the problem.