Does anyone know what the “T” is that is displayed next the “Radio” on the LCD display? I have a 05’ and when I turn on the radio or cd player I get a “REG ON” at first and then a “T” pops up next to the “Radio” on the display. This “T” is there whether I am playing the cd or radio. Sometimes the “T” will go out and then come back on. I’ve had the old cd player (upper) replaced and it seems like that’s when it starting do this. I am just curious why or what this is? Anyone have any idea. I could find anything in the manuals.