Radio froze sometimes it work sometimes it doesn’t

Hello, this sounds like it's something internal to the audio unit itself. It could be a software concern, but it's more likely to be unresolvable, as radios from 2011 were not as easily updated compared to today's units. Definitely make sure there are no devices plugged in or paired such as mobile phones or iPod's -- just to eliminate variables. A device plugged in can cause problems with the audio unit as well.