Radio/tape Cd Player problems of the 2007 Nissan Versa

Nissan Versa 2007. Some times the car won't start with the intelligent key. The car sometimes locks automatically and other times it won't lock with the intelligent key, I am afraid the car will lock with my grandchild in it and I can't open the car. I used the horn and the radio came on. I have taken the car to the dealer several times and thy can not find anything wrong, but there certainly is.

I had purchased a new 2007 Versa from star Nissan on 9/22/07. A couple of days later, I found out the cd player was non-functional. A day or two later, I realized I was having problems starting the car. On 9/26, I brought the car in to see what the problem was. I was told on 9/27 that it had a faulty fuel pump and that the part they needed won't be available until 10/10/07. Obviously, it is unacceptable for me to be without my brand new car for a week and a half.