You could try disconnecting the 12 volt battery. That should reset the radio.
You would need the radio code, but you can get that by going to a Honda web site and providing them your VIN and 'device serial number'. Here is the link if anyone needs that. Not sure if this is already in the maintenance section, but it could be added since it is pretty handy. You just fill in the info and submit and they email you a list of 5-10 possible codes. For some reason I had to try several and then one worked..