I have been unable to program my 15-1994 to operate my Pioneer Combiplayer (LD and DVD). The remote gives an invalid signal when I enter the 4 digit codes given by the manual and technical services. I have tried both aux1 and aux2. My other five components were no problem. Out of nine codes, it will recognize only one and respond with the double blink. All others give me the long single flash.

Any ideas?