jQuery checkbox script giving odd results

Script is supposed to check all hidden checkboxes when the main checkbox attribute is checked as TRUE. If it's left unchecked, or if user checks/unchecks, the same value should be applied for the hidden attributes.

It works fine 90% of times, but it seems in some cases (not sure how yet) it doesnt work, and some results come in where user has main checkbox as TRUE but all others as FALSE, and vice-versa.

Why does it happen?

 <script>      
             $(function() {
             var marketingMAIN= $("input[type='checkbox'][name='marketingMAIN']");
             var marketingPhone = $("input[type='hidden'][name='marketingPhone']");
             var marketingRobo = $("input[type='hidden'][name='marketingRobo']");
             var marketingSMS = $("input[type='hidden'][name='marketingSMS']");
             var marketingEmail = $("input[type='hidden'][name='marketingEmail']");
             var marketingIM = $("input[type='hidden'][name='marketingIM']");
             var marketingPush = $("input[type='hidden'][name='marketingPush']");
             var marketingPaperMail = $("input[type='hidden'][name='marketingPaperMail']");

             marketingMAIN.on('change', function()
               {
               if ($(this).val() == "TRUE")  {
                 marketingPhone.prop('checked',true);
                 marketingPhone.val('TRUE');
                 marketingRobo.prop('checked',true);
                 marketingRobo.val('TRUE');
                 marketingSMS.prop('checked',true);
                 marketingSMS.val('TRUE');
                 marketingEmail.prop('checked',true);
                 marketingEmail.val('TRUE');
                 marketingIM.prop('checked',true);
                 marketingIM.val('TRUE');
                 marketingPush.prop('checked',true);
                 marketingPush.val('TRUE');
                 marketingPaperMail.prop('checked',true);
                 marketingPaperMail.val('TRUE');
               } else {
                 marketingPhone.prop('checked',false);
                 marketingPhone.val('FALSE');
                 marketingRobo.prop('checked',false);
                 marketingRobo.val('FALSE');
                 marketingSMS.prop('checked',false);
                 marketingSMS.val('FALSE');
                 marketingEmail.prop('checked',false);
                 marketingEmail.val('FALSE');
                 marketingIM.prop('checked',false);
                 marketingIM.val('FALSE');
                 marketingPush.prop('checked',false);
                 marketingPush.val('FALSE');
                 marketingPaperMail.prop('checked',false);
                 marketingPaperMail.val('FALSE');
               }
             });
             });
          </script>

The hidden attributes are marked as follows:

           <input type="hidden" name="marketingPhone" value=""/>
           <input type="hidden" name="marketingRobo" value=""/>
           <input type="hidden" name="marketingSMS" value=""/>
           <input type="hidden" name="marketingEmail" value=""/>  
           <input type="hidden" name="marketingIM" value=""/>
           <input type="hidden" name="marketingPush" value=""/>
           <input type="hidden" name="marketingPaperMail" value=""/>