I´ve Problems with ATC sometimes too, mostly when Close to departure. For Example, I´m just 10 or 30 miles before Landing, flying at 15000 ft, and suddenly, there is still no Communication with ATC (sinking at 5000 or 2500 ft) and my Plane is missing the Runway, so i´ve to turn arround and landing manually. But this is not recorded to my Pilot Profil (Started, but not landed), i try to recieve new Orders, but Radio makes just a short noising (sounds like a scratch), and no answer… and Radio MHZ setting are still ok…