Mark, I hope you get to the root cause. Sometimes just tapping on a relay case will free welded contacts. I have seen residual magnetism keep industrial relays closed, but I doubt that's your problem. If the relay contacts should continue to deterioate, an open circuit may result and the radio will not come on when it should.
If a new relay is warranted, thankfully,WHITEXKR warned me a few years ago to use only genuine Jag ones as they have built-in transient spike protection for our delicate electronics.(Advance Auto relays did not)