There are 2 very obvious sources for your problem.
1) the inside radio REQUIRES an external antenna. Of it's not connected or improperly installed, the radio will behave as you described
2) the radio is Defective.
Either would require a trip back to your dealer for warranty repair
JMHO
Denny WA8SHC (Rita RIP 10/13)
Siberian Husky Tikanni (Ta'kya RIP 11/13 Princess RIP 10/04 Taz RIP 5/08)
2007 Dodge Ram 2500 Quad Cab 5.9L CTD 3.73/LSD,Edge Insight monitor
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