It might be related to the LaneWatch camera, some experimentation should be able to determine that. A related common complaint is some people don't like when they are signalling right but also want to view the navigation screen, but the LaneWatch camera blocks the view. There are two options, if you press the button at the end of the turn signal stalk it will turn off the camera until the next time you signal. As an alternative you can go into the settings and turn off the camera, in Settings -> Camera -> LaneWatch -> Show with Turn Signal, and change it to OFF. The camera will no longer automatically turn on when you use the right turn signal, however it can still be turned on at any time by pressing the button on the stalk. You may want to try setting it to OFF to see if this solves the text readout problem when signalling.
As a side note, the stalk button also allows you to turn the LaneWatch camera on at any time, even when not signalling. I often use it when I am planning to make a lane change at the next convenient opportunity, I turn on the camera so that I can safely monitor traffic in the right lane without constantly turning my head, then when I am ready to make the actual lane change of course I then use turn my head and look and also use the turn signal.
