If all 4 sub fields are text, then they will not be returning an object. Field types such as image, post object do.
Perhaps you could update your version of ACF to fix the issue? It is hard for me to debug and help solve an issue when the issue is occurring on an older version of ACF.
If you do not wish to update to ACF 4.2, perhaps you could update to 4.1.8? You can download all version on the WP website here:
If you can, please update to ACF 4.3.2
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