Hello all, I have the following problem: When giving gas, a small high sound becomes audible. The more gas the louder! He can also be heard in idle mode, but quite quiet. If the engine is out, you can’t hear it at all. That’s only occurred since I installed the Radio Roadstar CD-650 in my Opel Omega. What does it have to do with this high sound and how do I get it off. I have read on other pages what is caused by alternators, etc., and you could buy a kind of destroyer at Conrad for example. What’s that, helps that and where does it go? Then I have also read thrushes or other things like earth. Would I really be very happy about an answer, so it’s annoying! Do you know exactly what I need at Conrad for a part? Alternatively: since I’m not a hifi professional. I come from Cologne, does someone know a company that knows the problem and can repair it? Have called today at Opel Levi in Cologne, who said, but must be disturbed and can’t they?