Radio getting very hot to touch when on for an hour or more

What is your question?

When driving for an hour or more, the 2012 highlander screen on the radio will get hot enough to feel like it will burn you, when you touch it. It's only AM/FM - CD player, no GPS or touch screen. Display only. Iv'e tried not using heater in car to make sure it's not the heating system causing this and it still gets very hot. Is this going to catch fire ????

What makes this problem better or worse?

nothing so far

How long has your 2012 Toyota Highlander had this problem?

just did it for first time last night, 12/26/18