Weird one!
Take a look at the below, goes in advancedsettings.xml;
<loglevel>
The logging level that XBMC will use to log errors and information. Available values are:
-1 No logging, suppresses all log output
0 Normal logging, only logging errors (Default)
1 Debug logging
2 Debug logging with freemem, fps and cpu usage shown on screen
3 Debug logging with freemem, fps and cpu usage and full smb logging
NOTE: As of r22142, loglevel also accepts a "hide" boolean attribute. Default value is true (old behavior), which hides the "enable debugging" guisetting. When false, the "enable debugging" guisetting will switch between min(loglevel, 0) and max(loglevel, 2) for off and on respectively. This is useful for chasing infrequent bugs where you may always want a debug text log, yet still be able to get at the on screen debug info without restarting the app. Example:
<loglevel hide="false">2</loglevel>
Here is the link;
advancedsettings.xml
But also try the below before enabling debug mode.;
1. Make sure you have the latest AllinOne script installed.
2. If you have any TVShow playlists set as Main or SubMenu items remove them, will not go in to details but try and let us know.
EDIT: just took a second look and the advancedsettings options may not do what you want, do not have time to test myself so perhaps just give the options a go to see.
EDIT2: Try <loglevel hide="false">1</loglevel> I think this should enable debug mode without the info on the screen but make sure Debug is turned off in the actual menu. But this is not really a great solution as you need to find out what is causing this.