Audition not recording in waveform

Checked other posts, no joy.  I'm trying to record voice in mono via waveform, using Audient iD4, never previous probs but not used for a few months.  When I start new file and hit record, my green levels bar at the bottom shows that sound is being received as I speak, but no waveform appears on main screen and nothing is recorded.  All appears to be plugged in, input levels as usual, totally stuck and can't record.  Help!  PS  I'm very non-techie, just read books (audio narration) for charity, never music, so please speak to me as a dummy! Thanks, Kate