Better exposed filters allows only one checkbox at a time Im using a exposed filter in views. That filter is displayed as a checkbox using the BEF module. 
Im allowing multiple selection on that filter. 

The problem is that when a user click on multiple checkboxes at once it only selects one. Its like refreshing after you check one selection and then it scrols up the list. You can select more then one option, but not at once. 

And yea, Ajax is enebled. 

Anyone else has this kind of a problem?
Follow the steps: 


go to advanced tab.
Under exposed form section, go to exposed form style setting. (BEF settings).
Then under display option of your checkbox field, expand more options and check add select all/none option. 
Uncheck autosubmit option if checked.