Samsung PG19NSBU-ADC - Manual (Page 68)

User’s Manual
Troubleshooting
Q&A
Question Answer
The Highlight Zone's Size/Position
Size Tabs do not respond. Check if the Highlight Zone Full Screen function has been
used but not yet released. If Full Screen is on, those three
functions will not operate.
Note: If this problem persists, reinstall the program. If it still
persists, contact the Service Center.