I have a 2002 996 Carrera convertible. The battery is OK as are the key remotes. However, at times (1/5 or so), neither the remote key or the physical key will open the driver's door, and I have to open the passenger door, and reach in to open the driver's door side. Sometimes this works, and sometimes not. Also, on one occasion the rear spoiler did not retract, but then did so next time I took the car out. I checked the fuses, and they seem OK. Any ideas as to what is going on??