It's ages since I dabbled with the settings and it may vary with different images.
I'm sure it used to be in front panel settings.
Just have a browse through all the settings screens, it will be in there somewhere.
I'm at work so can't look myself.
found a fix for this , if anyone intereste here's how :
There is a plugin in extensions. ( permanent VDF clock)
Once you have downloaded then go back to plugins menu. Press ok on THE PLUGIN. Press right arrow on the first menu "activate permanent vid clock". Press green ok. Restart box.
The clock and date will show after a few seconds.