I have two SOLO units. One has the current firmware version (2.1.270) and works correctly. The other has an older firmware (2.1.120) and displays the wrong remote controls for the two devices connected to it (A Fios DVR and a ReplayTV DVR).
I've followed the instructions on how to upgrade the firmware several times, but it never takes me to the download screen. It tells me to install the "Slingplayer Desktop", but when I start that app, I just get a blank window and it hangs. I have to kill the process. I have the original Sling Player which works fine. And it has an option to update the firmware using a file on the hard drive. If I could just find a copy of the 2.1.270 firmware to download, I think everything will be OK.