Hey Brian,

This isn't possible currently but what you could do is to modify the theme file /media/com_easysocial/apps/fields/user/acymailing/themes/default/content.php and at line 17, locate the codes below:

[gist]
<input type="checkbox" name="<?php echo $inputName;?>" id="<?php echo $inputName;?>" value="1" <?php echo $value ? ' checked="checked"' :'';?> />
[/gist]

Replace it with,

[gist]
<?php
$value = $value === '' ? 1 : 0;
?>
<input type="checkbox" name="<?php echo $inputName;?>" id="<?php echo $inputName;?>" value="1" <?php echo $value ? ' checked="checked"' :'';?> />
[/gist]