So I brought my 2017 Optima GT LineS 2 years ago and all good. Now all of a sudden the DAB radio has stopped working. I can't get a signal anywhere, sometimes is does drop in but only very briefly. The AM radio works just fine and everything else is working just fine. I know it must be a radio fault as my wife's car (Mazda CX3) doesn't have a signal problem. Any ideas on what's suddenly caused the loss of signal?