X5 Radio problems

[ilkec]

Hi,
I write from the Croatian. Sorry to my knowledge of English
I'm have a problem with the audio part of the X5. It is from 2008.
When the radio is on, I cannot hear anything . Also see nothing happening while turning on the volume button. When I press the volume button I see in the display that the radio is in "mute" but if I press it again still no audio. Radio is CCC model.
Also with my navigation system, no audio only visible.
With my parking sensor it's also no audio, only visible.
I have first checked a both fuse box, and all the fuses are good.I was at the</SPAN> service, and they are the first check-in amplifier. They placed with second amplifier and say that the problem is in the radio. I do not want to change the radio, because I am not sure that is the problem. </SPAN>I read on the forums that the battery can be a problem. I changed the battery but I`m not reset it because I was afraid that everything does not block .. Electricity has been involved the whole time through another battery. And still no sound. We checked out the speakers in the vehicle and they are all ok
If anyone has experience with this problem and know the solution please help