Why can't I hear anything?

Installed the trial version of Cubase Elements 7; told it that POD HD is my primary audio interface; added a track with a VST instrument; added MIDI to the track; but I hear nothing? How to troubleshoot here?

Be more specific, …you hear nothing when you do what exactly?
How is it wired.
Did you enable the monitor button on the midi track?

Thanks very much. I can hear now. Using a 3rd-party VST instrument. I hear it when monitoring, playing back, and rendering. My earlier failure was attempting to use one of the built-in VST instruments, but now I have bearing on which to troubleshoot that specific problem.