I think I misunderstood your trouble symptoms, shimronfio.
If your problems occur with your radio-mounted controls, it may be you have a problem with your radio.
If you problems occur only with your steering wheel controls but your radio-mounted controls work fine, then your problem is likely with the steering wheel buttons and associated wiring. There is a procedure for checking this, and I'm sure it can be done by an individual with working knowledge of an Ohm meter to check electrical resistance.
I'm curious - has there been any change to your steering wheel, any damage or perhaps spilled liquids?
Any by the way, I was lucky to visit Tel Aviv years ago.
View my fuel log 2015 Mirage ES 1.2 manual: 50.1 mpg (US) ... 21.3 km/L ... 4.7 L/100 km ... 60.2 mpg (Imp)