No this is not a common fault with the F2-FOX T, I suggest you try a Default Setting and post back if the problem persists. Are you sure you can receive all the multiplexes with your existing aerial?
The F2-FOX T is a very good Freeview box but unfortunately Humax left the software in a poor state. If the software version is v12 or v13 you’ll find the programme information will disappear after a few hours running, the only way to get it back is to switch OFF the mains, wait 30 seconds(ish) and back ON again.