I have this 'No Signal ' message box issue in my C Max - Sirius XM has worked fine and still does - just this annoying meassge box. Sirius 'help' has been no help. I did the 'signal reactivation' with Sirius (which fix a different problem) but the 'No signal' continues. I see a reference to a Master Reset above. Is this a Sirius XM reset or a Sync reset? (or is it officially a MYTouch reset?)