w reg renault scenic megane radio code nightmare!?

Hi had a battey change on me renault the radio is now asking for the code. the handbook had a code which was wrong , a dealership gave me a code which is wrong and the place where i bought the car have advised they had replaced the unit and written the code on top of the unit in the car! anyway I have managed to get the unit out and have found the code written on top the machine. Alas due to the earlier cock up its taking an eternity for the error message to disapper so I can input the code. Is there any way to reset this timing or do i have to sit it out and wait?