In addition to the above:
Check the audio panel.
From real life experience, after the stated and obvious (volume, frequency, etc) check sockets first (i.e. try co-pilot's side, using RH PTT), they are the cause of much grief. Then try hand-held (if avail).
If still no joy and you must proceed w/o radio, check if any specific NORDO procedures are in place for the airport you are flying to. Published in the Jepp plates. If so, follow procedure and await light signals.