Another strange radio problem!

When using the steering wheel controls to move around the pre-set radio stations, something strange happens.

I'll press the down button and all the Audience unit will do is scroll down the 3 stations on the right - I keep pressing and sometimes it might just select the same pre-set a couple of times then keep moving down the same 3 pre-sets. Then it might jump to the other side of the screen and the 3 pre-sets there and then go through them only.

You would think that by pressing up it would scroll through pre-sets 1 to 6, or if you press down it will scroll through 6 to 1 (or whatever number pre-set you are on it might go 2/3/4/5/6/1 or 5/4/3/2/1/6).

Example:

I'm on pre-set no4 and I'll press the down arrow on the steering wheel, the radio will go 4/4/4/5/6/4/5/6/4/5/6/4/5/5/5/6 then it might jump over to 1 then go 1/2/3/1/2/3/1/2/3/3/3/1/2/2/2/3/4

Damm annoying when you only want the station 3 pre-sets away!

Is it my car only?