Commands out of sync; you can't run this command now

I've been trying to fix this or find a way round this with out disconnecting from the DB completely and re-connecting, but I'm having some real troubles with this error.

My function to run SQL is as follows...
(It's a function inside a class of mine)

if($objRecordset = $this->_DB->query($strSQL)){
	ShowDebug("Recordset = ". gettype($objRecordset));	
	if(is_object($objRecordset)){
		if($objRecordset->num_rows > 0){
			$i = 0;
			while($row = $objRecordset->fetch_assoc()){
				foreach($row as $field => $value){
            		$objRS[$i][$field] = stripslashes($value);
            	}
            	$i++;
            }
		}					
	}
	$objRecordset->close();
}

PHP:

Even though I'm closing the recordset, I'm still getting the same error.
Is there any thing obvious I'm not doing?

I really don't want to have to disconnect from the DB completely.