Session_start() PHP warning

Our previous host continually logged PHP warning errors for a session_start() even after headers were sent. New host narrows the issue to the following files in Simple Link Directory…

/qc-simple-link-directory/qc-op-directory-main.php on line 106
/qc-simple-link-directory/modules/claim_listing/class.sld_claim_listing_page.php on line 23

Is this considered normal behavior or perhaps a potential conflict with a plugin or theme? Is there a quick fix for this or an update forthcoming?

Thanks!

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