Battery Isolator and radio

[Island Dodge]

Has anyone ever had a problem with the battery isolator causing the radio to not come on, but only once in a great while. Heres the deal The PO of my truck bought a new duely in Idaho from a big dealer and wanted an isolator installed. The dealer said he wouldn't do it because they would/could cause radio problems... . Back to the "94" truck I just bought from him. 18 mo+- ago he had an isolator installed at a local RV shop. He told me what this dealer said about the isolator and sure enough I had a problem, radio wouldn't come on, no big deal but since I don't need and isolator I went back to the RV shop and the guy thinks I'm bonkers for thinking an isolator could be the problem, had him disconnect it anyway. I was just wondering if anyone else has had a problem??

 

[Island Dodge]

I should add that the Idaho dealer said it would have to do with the ground. He also sells another brand of truck, Chevys , I think, but the problem is only with Dodge. ????