Unity 5 UI Text Glitch (illegible characters)

Can anybody explain t$$anonymous$$s? Testing on (and screenshot from) Android 5.0.2, OnePlus One CyanogenOS.

Happens completely randomly.

T$$anonymous$$s is the code that updates the topmost text label:

 void Update () {        
         if (!_pc.IsDead) {
             CurrentScoreValue.text = "" + PlayerStats.Score;
             HighscoreValue.text = "Highscore: " + PlayerStats.Highscore;
         }
         else if (_pc.IsDead)
         {
             PanelFailedMenu.SetActive(true);
             FailedScoreValue.text = "" + PlayerStats.Score;
         }
     }

The bottom-most text label is never updated.

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