I have a Denon 1911 that skips when listening to HD radio. It is exactly like a scratched CD. Once I turn the receiver off and on it will work for another 15 to 30 minutes. All of the other inputs work fine. Any ideas on a cause? I thought it might be the antenna but I have tried an areal and a basic antenna. Should I tear the system down and send the receiver in under warranty or is there a issue with my setup? Denon had me reset defaults with no improvement.