Boot into recovery mode & select WIPE CACHE PARTITION & see if that'll do the trick.
Phone OFF,then simultaneously depress the VOLUME UP/POWER/HOME buttons.
Release once you see the boot screen w/the recovery header at the top of the page.
Wait for the GREEN ANDROID bot to appear & see a menu.
Using the VOLUME rocker,select WIPE CACHE PARTITION.Press the POWER button.
Then,you should again be at the top of the menu to re-boot.
Depress the POWER button to re-boot & you'll return to normal operations.
No worries,you won't lose one iota of information/data/contacts/etc.....