2000 Silverado poor radio reception
 

I have an issue with my 2000 Chevy Silverado's radio reception. If in acc or with the engine started in park, radio does fine. When the gear shifter is placed in ANY selection other than PARK, i lose reception of distant stations. Place the truck back in PARK, the distant stations come back. The original factory did this as well as the recently installed Kenwood DXP 742BH. Can anyone offer any suggestions why putting the truck in gear would reduce the radio reception? Thanks for any advise. John

update on earlier post.
The engine running does not degrade the weak signal reception. Only when the shift lever is removed from park to ANY other position does the rfi occur. Place the truck back in park and reception is good again. I removed the antenna base from the fender (3 bolts) and no corrosion or rust. I made a braid ground lead and grounded the antenna base to the firewall with no results. All battery connections are clean and tight. Antenna lead is tight into rear of radio. Only when the shifter is removed from the park position does the interferrance occur?

another update: 08/27/2017
My truck has No leds. I performed a test by placing the truck in gear with the truck engine NOT running. I did this by placing the trunk in park, turning the key to the on position, (radio on), then opening and closing the door, then moving shifter from PARK to the other selections. No RFI occured. When I cranked the truck, the RFI returned. When I turned the key off, The RFI remained til I opened and closed the door.