Back in 2007, I installed a Sirius tuner kit from Grubbs. It's the tuner where the antenna plugs directly into the tuner, no splitter. I also did the stealth antenna install under the liftgate spoiler. It's worked flawlessly until a few months ago when the radio started displaying "ANTENNA". I thought the antenna cable was probably pinched or damaged somewhere, but today I opened it up and tried a different antenna with the same results. Time for a new tuner?