Hi, I have had the problem for a long time that when driving over hard short ground waves or similarly caused jerks of the radio reception in the moment briefly “spotter”. With the old radio I already had this, but with the new one it is more noticeable because of the clearer sound. Is this the rear window antenna? Where is the switch box for the antenna? What do I have to change? The rear window probably not, because it will probably not have a wobble contact?! Thank you and greeting Markus